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/bluegiga/apx4devkit/apx4devkit.c b/board/bluegiga/apx4devkit/apx4devkit.c
index 2599db7..be8eefb 100644
--- a/board/bluegiga/apx4devkit/apx4devkit.c
+++ b/board/bluegiga/apx4devkit/apx4devkit.c
@@ -14,6 +14,7 @@
  */
 
 #include <common.h>
+#include <init.h>
 #include <net.h>
 #include <asm/gpio.h>
 #include <asm/io.h>