common: Drop init.h from common header

Move this uncommon header out of the common header.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/arm/mach-imx/cpu.c b/arch/arm/mach-imx/cpu.c
index 468c2fa..92db8ac 100644
--- a/arch/arm/mach-imx/cpu.c
+++ b/arch/arm/mach-imx/cpu.c
@@ -8,6 +8,7 @@
 
 #include <bootm.h>
 #include <common.h>
+#include <init.h>
 #include <net.h>
 #include <netdev.h>
 #include <linux/errno.h>