tests/tcg: skip the vma-pthread test on CI

We are getting a lot of failures that are not related to changes so
this could be a flaky test.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20230124180127.1881110-16-alex.bennee@linaro.org>

tests/tcg/multiarch/Makefile.target

@@ -42,6 +42,15 @@ munmap-pthread: LDFLAGS+=-pthread
 vma-pthread: CFLAGS+=-pthread
 vma-pthread: LDFLAGS+=-pthread
 
+# The vma-pthread seems very sensitive on gitlab and we currently
+# don't know if its exposing a real bug or the test is flaky.
+ifneq ($(GITLAB_CI),)
+run-vma-pthread: vma-pthread
+	$(call skip-test, $<, "flaky on CI?")
+run-plugin-vma-pthread-with-%: vma-pthread
+	$(call skip-test, $<, "flaky on CI?")
+endif
+
 # We define the runner for test-mmap after the individual
 # architectures have defined their supported pages sizes. If no
 # additional page sizes are defined we only run the default test.