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-at91/arm926ejs/cpu.c b/arch/arm/mach-at91/arm926ejs/cpu.c
index e9b4e06..761edb6 100644
--- a/arch/arm/mach-at91/arm926ejs/cpu.c
+++ b/arch/arm/mach-at91/arm926ejs/cpu.c
@@ -7,6 +7,7 @@
  */
 
 #include <common.h>
+#include <init.h>
 #include <vsprintf.h>
 #include <asm/io.h>
 #include <asm/arch/hardware.h>