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/ti/ks2_evm/board_k2e.c b/board/ti/ks2_evm/board_k2e.c
index 350cc68..39abb24 100644
--- a/board/ti/ks2_evm/board_k2e.c
+++ b/board/ti/ks2_evm/board_k2e.c
@@ -8,6 +8,7 @@
 
 #include <common.h>
 #include <image.h>
+#include <init.h>
 #include <asm/arch/ddr3.h>
 #include <asm/arch/hardware.h>
 #include <asm/ti-common/keystone_net.h>