selftests: mptcp: fix error path

BugLink: https://bugs.launchpad.net/bugs/2083488

commit 4a2f48992ddf4b8c2fba846c6754089edae6db5a upstream.

pm_nl_check_endpoint() currently calls an not existing helper
to mark the test as failed. Fix the wrong call.

Fixes: 03668c65d1 ("selftests: mptcp: join: rework detailed report")
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[koichiroden: adjusted context due to missing upstream commits:
571d79664a4a ("selftests: mptcp: join: update endpoint ops")
commit 0d16e ("selftests: mptcp: add {get,format}_endpoint(s) helpers")]
Signed-off-by: Koichiro Den <koichiro.den@canonical.com>
Signed-off-by: Roxana Nicolescu <roxana.nicolescu@canonical.com>

tools/testing/selftests/net/mptcp/mptcp_join.sh

@@ -795,7 +795,7 @@ pm_nl_check_endpoint()
 	done
 
 	if [ -z "$id" ]; then
-		test_fail "bad test - missing endpoint id"
+		fail_test "bad test - missing endpoint id"
 		return
 	fi