[POWERPC] Add bootwrapper support for Marvell MPSC

The bootwrapper requires a serial driver to allow cmdline editing
and information reporting on the console.  This driver is required
by platforms that boot a zImage and use the MPSC for the console.

Signed-off-by: Mark A. Greer <mgreer@mvista.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
diff --git a/arch/powerpc/boot/serial.c b/arch/powerpc/boot/serial.c
index e8de4cf..7fd3233 100644
--- a/arch/powerpc/boot/serial.c
+++ b/arch/powerpc/boot/serial.c
@@ -125,6 +125,8 @@
 
 	if (!strcmp(compat, "ns16550"))
 		rc = ns16550_console_init(devp, &serial_cd);
+	else if (!strcmp(compat, "marvell,mpsc"))
+		rc = mpsc_console_init(devp, &serial_cd);
 
 	/* Add other serial console driver calls here */