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/board/amlogic/s400/s400.c b/board/amlogic/s400/s400.c
index 79b8679..7e2f0cd 100644
--- a/board/amlogic/s400/s400.c
+++ b/board/amlogic/s400/s400.c
@@ -6,6 +6,7 @@
 
 #include <common.h>
 #include <dm.h>
+#include <init.h>
 #include <net.h>
 #include <asm/io.h>
 #include <asm/arch/axg.h>