Fix compilation warnings.

... found by compiling them with gcc 2.95.
Signed-off-by: NJunio C Hamano <junkio@cox.net>

commit.c

@@ -357,7 +357,7 @@ static int get_one_line(const char *msg, unsigned long len)
 static int add_user_info(const char *what, enum cmit_fmt fmt, char *buf, const char *line)
 {
 	char *date;
-	unsigned int namelen;
+	int namelen;
 	unsigned long time;
 	int tz, ret;
 

diff.c

@@ -704,7 +704,7 @@ static int parse_num(const char **cp_p)
 			scale *= 10;
 			num = num * 10 + ch - '0';
 		}
-		*cp++;
+		cp++;
 	}
 	*cp_p = cp;