This reverts commit ad59322ae432d11ff36dcf046016af8cfe45fbe4
somehow my unfinished libm/Android.mk change got into here.
Change-Id: I46be626c5269d60fb1ced9862f2ebaa380b4e0af
This was originally motivated by noticing that we were setting the
wrong bits for the well-known tls entries. That was a harmless bug
because none of the well-known tls entries has a destructor, but
it's best not to leave land mines lying around.
Also add some missing POSIX constants, a new test, and fix
pthread_key_create's return value when we hit the limit.
Change-Id: Ife26ea2f4b40865308e8410ec803b20bcc3e0ed1
