selftests: android: move config up a level

'make kselftest-merge' assumes that the config files for the tests are
located under the 'main' test dir, like tools/testing/selftests/android/
and not in a subdir to android.

Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Signed-off-by: Shuah Khan (Samsung OSG) <shuah@kernel.org>