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/drivers/serial/altera_uart.c b/drivers/serial/altera_uart.c
index 27550ed..118cd58 100644
--- a/drivers/serial/altera_uart.c
+++ b/drivers/serial/altera_uart.c
@@ -82,13 +82,6 @@
 	writel ((unsigned char)c, &uart->txdata);
 }
 
-static void altera_serial_puts(const char *s)
-{
-	while (*s != 0) {
-		serial_putc (*s++);
-	}
-}
-
 static int altera_serial_tstc(void)
 {
 	return (readl (&uart->status) & NIOS_UART_RRDY);
@@ -107,7 +100,7 @@
 	.stop	= NULL,
 	.setbrg	= altera_serial_setbrg,
 	.putc	= altera_serial_putc,
-	.puts	= altera_serial_puts,
+	.puts	= default_serial_puts,
 	.getc	= altera_serial_getc,
 	.tstc	= altera_serial_tstc,
 };