Sources and Docs: Fix typos and nxstyle issues

Documentation/contributing/coding_style.rst:

    * Fix repeated words: ("this this").
    * Remove trailing spaces.

boards/z80/z80/z80sim/README.txt:

    * Fix repeated words: ("this this") and rewrap lines.

graphics/Kconfig,
libs/libc/math/Kconfig:

    * Fix repeated words: ("this this").

arch/arm/src/armv7-a/arm_assert.c,
arch/arm/src/armv7-r/arm_assert.c,
arch/arm/src/imxrt/imxrt_enet.c,
arch/arm/src/kinetis/kinetis_enet.c,
arch/arm/src/kinetis/kinetis_flexcan.c,
arch/arm/src/s32k1xx/s32k1xx_enet.c,
arch/arm/src/s32k1xx/s32k1xx_flexcan.c,
arch/arm/src/stm32/stm32_pwm.c,
arch/arm/src/stm32h7/stm32_pwm.c,
arch/arm/src/stm32l4/stm32l4_pwm.c,
arch/renesas/src/rx65n/rx65n_usbdev.c,
binfmt/libnxflat/libnxflat_bind.c,
drivers/pipes/pipe_common.c,
net/igmp/igmp_input.c,
net/tcp/tcp_conn.c,
sched/sched/sched_roundrobin.c:

    * Fix typo in comment ("this this").

arch/arm/src/cxd56xx/cxd56_usbdev.c,
arch/arm/src/lc823450/lc823450_usbdev.c:

    * Fix typo in comment and rewrap lines.

arch/arm/src/imxrt/imxrt_usbdev.c,
arch/arm/src/stm32/stm32_dac.c,
arch/arm/src/stm32f0l0g0/stm32_pwm.c,
arch/arm/src/stm32f7/stm32_pwm.c,
arch/arm/src/tiva/lm/lm4f_gpio.h,
fs/nxffs/nxffs_write.c,
include/nuttx/analog/pga11x.h,
include/nuttx/usb/usbdev.h,
net/mld/mld_join.c:

    * Fix typo in comment ("this this").
    * Fix nxstyle issues.

net/igmp/igmp_input.c

@@ -178,7 +178,7 @@ void igmp_input(struct net_driver_s *dev)
 
         if (net_ipv4addr_cmp(destipaddr, g_ipv4_allsystems))
           {
-            /* Yes... Now check the if this this is a general or a group
+            /* Yes... Now check the if this is a general or a group
              * specific query.
              *
              * RFC 2236, 2.1.  Type

net/mld/mld_join.c

@@ -13,21 +13,21 @@
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
- * 3. Neither the name of CITEL Technologies Ltd nor the names of its contributors
- *    may be used to endorse or promote products derived from this software
- *    without specific prior written permission.
+ * 3. Neither the name of CITEL Technologies Ltd nor the names of its
+ *    contributors may be used to endorse or promote products derived from
+ *    this software without specific prior written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY CITEL TECHNOLOGIES AND CONTRIBUTORS ``AS IS''
  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
- * ARE DISCLAIMED.  IN NO EVENT SHALL CITEL TECHNOLOGIES OR CONTRIBUTORS BE LIABLE
- * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
- * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
- * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
- * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
- * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
+ * ARE DISCLAIMED.  IN NO EVENT SHALL CITEL TECHNOLOGIES OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
  *
  ****************************************************************************/
 
@@ -184,7 +184,7 @@ int mld_joingroup(FAR const struct ipv6_mreq *mrec)
           return -ENOMEM;
         }
 
-      /* Indicate one request to join the group from this this host */
+      /* Indicate one request to join the group from this host */
 
       group->njoins = 1;
 
@@ -241,7 +241,7 @@ int mld_joingroup(FAR const struct ipv6_mreq *mrec)
       DEBUGASSERT(group->njoins > 0);
 #endif
 
-      /* Indicate one more request to join the group from this this host */
+      /* Indicate one more request to join the group from this host */
 
       DEBUGASSERT(group->njoins < UINT8_MAX);
       group->njoins++;

net/tcp/tcp_conn.c

@@ -99,7 +99,7 @@ static dq_queue_t g_active_tcp_connections;
  *
  * Description:
  *   Given a local port number (in network byte order), find the TCP
- *   connection that listens on this this port.
+ *   connection that listens on this port.
  *
  *   Primary uses: (1) to determine if a port number is available, (2) to
  *   To identify the socket that will accept new connections on a local port.
@@ -150,7 +150,7 @@ static inline FAR struct tcp_conn_s *tcp_ipv4_listener(in_addr_t ipaddr,
  *
  * Description:
  *   Given a local port number (in network byte order), find the TCP
- *   connection that listens on this this port.
+ *   connection that listens on this port.
  *
  *   Primary uses: (1) to determine if a port number is available, (2) to
  *   To identify the socket that will accept new connections on a local port.
@@ -201,7 +201,7 @@ tcp_ipv6_listener(const net_ipv6addr_t ipaddr, uint16_t portno)
  *
  * Description:
  *   Given a local port number (in network byte order), find the TCP
- *   connection that listens on this this port.
+ *   connection that listens on this port.
  *
  *   Primary uses: (1) to determine if a port number is available, (2) to
  *   To identify the socket that will accept new connections on a local port.