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/sbc8349/pci.c b/board/sbc8349/pci.c
index b173c9c..b6435f3 100644
--- a/board/sbc8349/pci.c
+++ b/board/sbc8349/pci.c
@@ -7,6 +7,7 @@
  * Based on MPC8349 PCI support but w/o PIB related code.
  */
 
+#include <init.h>
 #include <asm/mmu.h>
 #include <asm/io.h>
 #include <common.h>