driver/serial: Convert CR to LF in driver

Enable the behavior by default for console,
but configurable by termios.

Binary size:

Before:
   text    data     bss     dec     hex filename
 326460     409    8164  335033   51cb9 nuttx/nuttx

 After:
    text    data     bss     dec     hex filename
 326478     409    8164  335051   51ccb nuttx/nuttx

Signed-off-by: Huang Qi <huangqi3@xiaomi.com>

drivers/serial/serial.c

@@ -790,6 +790,11 @@ static ssize_t uart_read(FAR struct file *filep,
            * IUCLC - Not Posix
            * IXON/OXOFF - no xon/xoff flow control.
            */
+#else
+          if (dev->isconsole && ch == '\r')
+            {
+              ch = '\n';
+            }
 #endif
 
           /* Store the received character */
@@ -1423,7 +1428,6 @@ static int uart_ioctl(FAR struct file *filep, int cmd, unsigned long arg)
               dev->tc_iflag = termiosp->c_iflag;
               dev->tc_oflag = termiosp->c_oflag;
               dev->tc_lflag = termiosp->c_lflag;
-
               ret = 0;
             }
             break;
@@ -1659,6 +1663,10 @@ int uart_register(FAR const char *path, FAR uart_dev_t *dev)
       /* Enable \n -> \r\n translation for the console */
 
       dev->tc_oflag = OPOST | ONLCR;
+
+      /* Convert CR to LF by default for console */
+
+      dev->tc_iflag |= ICRNL;
     }
 #endif