8641hpcn: Do correct sized pointer math.

When I rebased Ed's patch and cleaned up a few compilation
problems, I apparently rebased my brain on crack first.
Fix that by doing (char *) sized pointer math as needed.

Signed-off-by: Jon Loeliger <jdl@freescale.com>
diff --git a/board/mpc8641hpcn/mpc8641hpcn.c b/board/mpc8641hpcn/mpc8641hpcn.c
index d2182ab..1bfbe88 100644
--- a/board/mpc8641hpcn/mpc8641hpcn.c
+++ b/board/mpc8641hpcn/mpc8641hpcn.c
@@ -268,8 +268,8 @@
 		 * Activate ULI1575 legacy chip by performing a fake
 		 * memory access.  Needed to make ULI RTC work.
 		 */
-		in_be32((unsigned *) CFG_PCI1_MEM_BASE
-			+ CFG_PCI1_MEM_SIZE - 0x1000000);
+		in_be32((unsigned *) ((char *)(CFG_PCI1_MEM_BASE
+				       + CFG_PCI1_MEM_SIZE - 0x1000000)));
 
 	} else {
 		puts("PCI-EXPRESS 1: Disabled\n");