test-parse-options.c: fix style of comparison with zero

The preferred style is '!argc' instead of 'argc == 0'.

Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

t/helper/test-parse-options.c

@@ -255,7 +255,7 @@ int cmd__parse_options_flags(int argc, const char **argv)
 	argc = parse_options(argc, argv, NULL, test_flag_options, usage,
 			     PARSE_OPT_STOP_AT_NON_OPTION);
 
-	if (argc == 0 || strcmp(argv[0], "cmd")) {
+	if (!argc || strcmp(argv[0], "cmd")) {
 		error("'cmd' is mandatory");
 		usage_with_options(usage, test_flag_options);
 	}
@@ -313,7 +313,7 @@ int cmd__parse_subcommand(int argc, const char **argv)
 	argc = parse_options(argc, argv, NULL, test_flag_options, usage,
 			     PARSE_OPT_STOP_AT_NON_OPTION);
 
-	if (argc == 0 || strcmp(argv[0], "cmd")) {
+	if (!argc || strcmp(argv[0], "cmd")) {
 		error("'cmd' is mandatory");
 		usage_with_options(usage, test_flag_options);
 	}