Revert "Remove harmful attempts to be helpful in pthread_mutex functions."

This reverts commit 53f15d0325feeaf7e58dc79fce4ddf55e0a64b7a.
Merge branch 'cm-11.0' of git://github.com/CyanogenMod/android_bionic into kk44
Merge branch 'kk44' of https://github.com/scotthartbti/android_bionic into kk44