Fix/suppress unittests broken on Android

cctest/test-threads/ThreadJoinSelf is suppressed for Android, but the
test has since been moved to unittests/Thread.SelfJoin. Move the
suppression to unittests.status.

unittests/ThreadLocalStorageTest.DoTest fails on older Android devices
as it assumes the availability of more TLS slots than many devices
implement. Test a smaller number of slots (32) on Android. Remove old
suppression of test-platform-tls/FastTLS (which no longer exists).

cctest/test-mark-compact/RegressJoinThreadsOnIsolateDeinit can't deal
with shared mappings. Check for 's' instead of '-'.

BUG=v8:3706
LOG=

Review URL: https://codereview.chromium.org/735863003

Cr-Commit-Position: refs/heads/master@{#25492}