mktree: drop unused length parameter

The mktree_line() function does not actually look at the "len" parameter
it is passed, and assumes the buffer it receives is NUL-terminated.
Since the caller always passes a strbuf, this will be true. Let's drop
the useless parameter.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/mktree.c

@@ -67,7 +67,7 @@ static const char *mktree_usage[] = {
 	NULL
 };
 
-static void mktree_line(char *buf, size_t len, int nul_term_line, int allow_missing)
+static void mktree_line(char *buf, int nul_term_line, int allow_missing)
 {
 	char *ptr, *ntr;
 	const char *p;
@@ -172,7 +172,7 @@ int cmd_mktree(int ac, const char **av, const char *prefix)
 					break;
 				die("input format error: (blank line only valid in batch mode)");
 			}
-			mktree_line(sb.buf, sb.len, nul_term_line, allow_missing);
+			mktree_line(sb.buf, nul_term_line, allow_missing);
 		}
 		if (is_batch_mode && got_eof && used < 1) {
 			/*