Fix byte_cas to use uintptr_t Atomic.
Fix byte_cas to use uintptr_t Atomic.

Previously we used int32_t Atomic with a uintptr_t bit shift.
This was a mismatch on 64 bit and resulted in occasionally
having the cas return without having succeeded.

Bug: 16819816

(cherry picked from commit aa3c3e5ee83c061e7f387c75b1b29c9f248ac39c)

Change-Id: Ib97bf5880153ddfacf52409be3e9e821657bac59

treadstoneproject/artinst,treadstoneproject/artinst,treadstoneproject/artinst,treadstoneproject/artinst,treadstoneproject/artinst