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/liebherr/xea/xea.c b/board/liebherr/xea/xea.c
index 95c9064..41fa212 100644
--- a/board/liebherr/xea/xea.c
+++ b/board/liebherr/xea/xea.c
@@ -15,6 +15,7 @@
 
 #include <common.h>
 #include <fdt_support.h>
+#include <init.h>
 #include <net.h>
 #include <asm/gpio.h>
 #include <asm/io.h>