sub-process: do not use strbuf_split*()

The code to read status from subprocess reads one packet line and
tries to find "status=<foo>".  It is way overkill to split the line
into an array of two strbufs to extract <foo>.

Signed-off-by: Junio C Hamano <gitster@pobox.com>

sub-process.c

@@ -30,23 +30,20 @@ struct subprocess_entry *subprocess_find_entry(struct hashmap *hashmap, const ch
 
 int subprocess_read_status(int fd, struct strbuf *status)
 {
-	struct strbuf **pair;
-	char *line;
 	int len;
 
 	for (;;) {
+		char *line;
+		const char *value;
+
 		len = packet_read_line_gently(fd, NULL, &line);
 		if ((len < 0) || !line)
 			break;
-		pair = strbuf_split_str(line, '=', 2);
-		if (pair[0] && pair[0]->len && pair[1]) {
+		if (skip_prefix(line, "status=", &value)) {
 			/* the last "status=<foo>" line wins */
-			if (!strcmp(pair[0]->buf, "status=")) {
-				strbuf_reset(status);
-				strbuf_addbuf(status, pair[1]);
-			}
+			strbuf_reset(status);
+			strbuf_addstr(status, value);
 		}
-		strbuf_list_free(pair);
 	}
 
 	return (len < 0) ? len : 0;