btrfs: tests: fix return 0 on rmap test failure

In test_rmap_blocks(), we have ret = 0 before checking the results. We need
to set it to -EINVAL, so that a mismatching result will return -EINVAL not
0.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

Author: naota

fs/btrfs/tests/extent-map-tests.c

@@ -1059,19 +1059,22 @@ static int test_rmap_block(struct btrfs_fs_info *fs_info,
 
 	if (out_stripe_len != BTRFS_STRIPE_LEN) {
 		test_err("calculated stripe length doesn't match");
+		ret = -EINVAL;
 		goto out;
 	}
 
 	if (out_ndaddrs != test->expected_mapped_addr) {
 		for (i = 0; i < out_ndaddrs; i++)
 			test_msg("mapped %llu", logical[i]);
 		test_err("unexpected number of mapped addresses: %d", out_ndaddrs);
+		ret = -EINVAL;
 		goto out;
 	}
 
 	for (i = 0; i < out_ndaddrs; i++) {
 		if (logical[i] != test->mapped_logical[i]) {
 			test_err("unexpected logical address mapped");
+			ret = -EINVAL;
 			goto out;
 		}
 	}