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/common/spl/spl.c b/common/spl/spl.c
index b33905e..6b1d41e 100644
--- a/common/spl/spl.c
+++ b/common/spl/spl.c
@@ -13,6 +13,7 @@
 #include <dm.h>
 #include <handoff.h>
 #include <hang.h>
+#include <init.h>
 #include <irq_func.h>
 #include <serial.h>
 #include <spl.h>