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/arch/mips/cpu/mips32/incaip/asc_serial.c b/arch/mips/cpu/mips32/incaip/asc_serial.c
index 08949f4..6f0e4f2 100644
--- a/arch/mips/cpu/mips32/incaip/asc_serial.c
+++ b/arch/mips/cpu/mips32/incaip/asc_serial.c
@@ -236,14 +236,6 @@
     }
 }
 
-static void asc_serial_puts(const char *s)
-{
-    while (*s)
-    {
-	serial_putc (*s++);
-    }
-}
-
 static int asc_serial_getc(void)
 {
     ulong symbol_mask;
@@ -292,7 +284,7 @@
 	.stop	= NULL,
 	.setbrg	= asc_serial_setbrg,
 	.putc	= asc_serial_putc,
-	.puts	= asc_serial_puts,
+	.puts	= default_serial_puts,
 	.getc	= asc_serial_getc,
 	.tstc	= asc_serial_tstc,
 };