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/highbank/highbank.c b/board/highbank/highbank.c
index ffde116..063831d 100644
--- a/board/highbank/highbank.c
+++ b/board/highbank/highbank.c
@@ -8,6 +8,7 @@
 #include <cpu_func.h>
 #include <env.h>
 #include <fdt_support.h>
+#include <init.h>
 #include <net.h>
 #include <netdev.h>
 #include <scsi.h>