selftests: clone3: use SKIP instead of XFAIL

XFAIL is gone since commit 9847d24a ("selftests/harness: Refactor XFAIL
into SKIP"), use SKIP instead.

Fixes: 9847d24a ("selftests/harness: Refactor XFAIL into SKIP")
Signed-off-by: NTommi Rantala <tommi.t.rantala@nokia.com>
Reviewed-by: NKees Cook <keescook@chromium.org>
Acked-by: NChristian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: NShuah Khan <skhan@linuxfoundation.org>

tools/testing/selftests/clone3/clone3_cap_checkpoint_restore.c

@@ -145,7 +145,7 @@ TEST(clone3_cap_checkpoint_restore)
 	test_clone3_supported();
 
 	EXPECT_EQ(getuid(), 0)
-		XFAIL(return, "Skipping all tests as non-root\n");
+		SKIP(return, "Skipping all tests as non-root");
 
 	memset(&set_tid, 0, sizeof(set_tid));