common: Move ll_boot_init() to init.h

This is an init-related function so belongs in that file. Move it.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/video/broadwell_igd.c b/drivers/video/broadwell_igd.c
index e6df037..c23421d 100644
--- a/drivers/video/broadwell_igd.c
+++ b/drivers/video/broadwell_igd.c
@@ -8,6 +8,7 @@
 #include <common.h>
 #include <bios_emul.h>
 #include <dm.h>
+#include <init.h>
 #include <vbe.h>
 #include <video.h>
 #include <asm/cpu.h>