MXC: add basic MXC91231 support

Signed-off-by: Dmitriy Taychenachev <dimichxp@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
diff --git a/arch/arm/Makefile b/arch/arm/Makefile
index 95ba3c5..c1d6003 100644
--- a/arch/arm/Makefile
+++ b/arch/arm/Makefile
@@ -159,6 +159,7 @@
 machine-$(CONFIG_ARCH_VERSATILE)	:= versatile
 machine-$(CONFIG_ARCH_W90X900)		:= w90x900
 machine-$(CONFIG_FOOTBRIDGE)		:= footbridge
+machine-$(CONFIG_ARCH_MXC91231)		:= mxc91231
 
 # Platform directory name.  This list is sorted alphanumerically
 # by CONFIG_* macro name.