serial: Use default_serial_puts() in drivers

Replace the in-place ad-hoc implementation of serial_puts() within
the drivers with default_serial_puts() call. This cuts down on the
code duplication quite a bit.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Marek Vasut <marek.vasut@gmail.com>
Cc: Tom Rini <trini@ti.com>
diff --git a/board/evb64260/serial.c b/board/evb64260/serial.c
index 9fd4298..b9ca1d7 100644
--- a/board/evb64260/serial.c
+++ b/board/evb64260/serial.c
@@ -139,20 +139,13 @@
 
 #endif /* CONFIG_MPSC */
 
-static void evb64260_serial_puts(const char *s)
-{
-	while (*s) {
-		serial_putc (*s++);
-	}
-}
-
 static struct serial_device evb64260_serial_drv = {
 	.name	= "evb64260_serial",
 	.start	= evb64260_serial_init,
 	.stop	= NULL,
 	.setbrg	= evb64260_serial_setbrg,
 	.putc	= evb64260_serial_putc,
-	.puts	= evb64260_serial_puts,
+	.puts	= default_serial_puts,
 	.getc	= evb64260_serial_getc,
 	.tstc	= evb64260_serial_tstc,
 };