bionic: update memmove for 32 bits atomic

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

Change-Id: I21cb77451270d061b32e3e2d2fda22e7e373b7ff
Merge pull request #3 from CyanogenMod/cm-11.0

bionic: update memmove for 32 bits atomic