bionic libc test: clean up test_static_cpp_mutex test

delete related file and setting for test test_static_cpp_mutex,
since it is migrated into bionic/tests/pthread_test.cpp in gtest format

Change-Id: Ia9d165b18410c40a6f07a3b0b23d53bf8e355d05
Signed-off-by: Yongqin Liu <yongqin.liu@linaro.org>
2 files changed