common: Move pci_init_board() out of common.h

This function can be dropped when all boards use driver model for PCI. For
now, move it into init.h with a comment.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@konsulko.com>
diff --git a/board/mpc8308_p1m/mpc8308_p1m.c b/board/mpc8308_p1m/mpc8308_p1m.c
index ab724da..5b2fd9c 100644
--- a/board/mpc8308_p1m/mpc8308_p1m.c
+++ b/board/mpc8308_p1m/mpc8308_p1m.c
@@ -6,6 +6,7 @@
 
 #include <common.h>
 #include <i2c.h>
+#include <init.h>
 #include <linux/libfdt.h>
 #include <fdt_support.h>
 #include <pci.h>