bionic: update memmove for 32 bits atomic

When src/dst are 32bits aligned, the updated memmove will guarantee
32bits atomic.

Change-Id: I21cb77451270d061b32e3e2d2fda22e7e373b7ff
Merge branch 'cm-11.0' of https://github.com/CyanogenMod/android_bionic into kitkat