ARM: imx: fold serial.c into devices.c

... and use cpp magic to reduce repetition.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
diff --git a/arch/arm/mach-imx/Makefile b/arch/arm/mach-imx/Makefile
index 068f493..9d57ba6 100644
--- a/arch/arm/mach-imx/Makefile
+++ b/arch/arm/mach-imx/Makefile
@@ -4,7 +4,7 @@
 
 # Object file lists.
 
-obj-y	:=  devices.o serial.o
+obj-y	:=  devices.o
 
 obj-$(CONFIG_MACH_MX21) += clock-imx21.o mm-imx21.o