Remove all void-pointer arithmetic.

ANSI C99 doesn't allow void-pointer arithmetic. This patch fixes this in
various ways. Usually the strategy that required the least changes was used.

Signed-off-by: Florian Forster <octo@verplant.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
diff --git a/patch-delta.c b/patch-delta.c
index 8f318ed..e3a1d42 100644
--- a/patch-delta.c
+++ b/patch-delta.c
@@ -25,7 +25,7 @@
 		return NULL;
 
 	data = delta_buf;
-	top = delta_buf + delta_size;
+	top = (const unsigned char *) delta_buf + delta_size;
 
 	/* make sure the orig file size matches what we expect */
 	size = get_delta_hdr_size(&data, top);
@@ -56,7 +56,7 @@
 			    cp_off + cp_size > src_size ||
 			    cp_size > size)
 				goto bad;
-			memcpy(out, src_buf + cp_off, cp_size);
+			memcpy(out, (char *) src_buf + cp_off, cp_size);
 			out += cp_size;
 			size -= cp_size;
 		} else if (cmd) {