This commit corrects a problem with NSH: NSH was calling the OS internal function ramdisk_register() in violation of the portable POSIX interface. This commit solves the problem by introducing a new boardctl() function BOARDIOC_MKRD which moves the RAM disk creation into the OS.

Squashed commit of the following:

    drivers/:  Run tools/nxstyle against all drivers/*.c.

    boards/boardctl.c:  Add new boardctl() command, BOARDIOC_MKRD, that can be used to create a RAM disk.  This will replace the illegal call to ramdisk_register() currently used by NSH.

    drivers/mkrd.c:  Add wrapper around ramdisk_register() for creating a proper ramdisk.

drivers/dev_null.c

@@ -86,7 +86,8 @@ static const struct file_operations devnull_fops =
  * Name: devnull_read
  ****************************************************************************/
 
-static ssize_t devnull_read(FAR struct file *filep, FAR char *buffer, size_t len)
+static ssize_t devnull_read(FAR struct file *filep, FAR char *buffer,
+                            size_t len)
 {
   return 0; /* Return EOF */
 }
@@ -95,7 +96,8 @@ static ssize_t devnull_read(FAR struct file *filep, FAR char *buffer, size_t len
  * Name: devnull_write
  ****************************************************************************/
 
-static ssize_t devnull_write(FAR struct file *filep, FAR const char *buffer, size_t len)
+static ssize_t devnull_write(FAR struct file *filep, FAR const char *buffer,
+                             size_t len)
 {
   return len; /* Say that everything was written */
 }