logd: test: logd.sepolicy* errors

If setcon fails, try alternate setcon, and then if it still
fails call getcon to confirm if it is an OK sepolicy context
anyways.

Test: gTest logd-unit-tests --gtest_filter=logd.sepolicy*
Change-Id: Iaf20b8a1a4a7312247288e1879884a54893c15ae