Avoid C99 comments, use old-style C comments instead.

This doesn't make the code uglier or harder to read, yet it makes the
code more portable.  This also simplifies checking for other potential
incompatibilities.  "gcc -std=c89 -pedantic" can flag many incompatible
constructs as warnings, but C99 comments will cause it to emit an error.

Signed-off-by: Pavel Roskin <proski@gnu.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
diff --git a/mktag.c b/mktag.c
index f0fe528..27f4c4f 100644
--- a/mktag.c
+++ b/mktag.c
@@ -17,7 +17,7 @@
  * in that size, you're doing something wrong.
  */
 
-// Some random size
+/* Some random size */
 #define MAXSIZE (8192)
 
 /*
@@ -123,7 +123,8 @@
 		die("could not read from stdin");
 	}
 
-	// Verify it for some basic sanity: it needs to start with "object <sha1>\ntype\ntagger "
+	/* Verify it for some basic sanity: it needs to start with
+	   "object <sha1>\ntype\ntagger " */
 	if (verify_tag(buffer, size) < 0)
 		die("invalid tag signature file");