Revert "libgralloc: Allow USAGE_RARELY flags to be uncached"

This reverts commit 94d54cb91047c2d06f41e8ee6a118ed902e96911.
Revert "gralloc: Allow system heap to be uncached."

This reverts commit 5836c13af8ace200095d68ef2494b7d8cff1e917.
libcopybit: bringback COPYBIT_PREMULTIPLIED_ALPHA

hwc 1.0 still need this

Change-Id: Idd1a5320b35193a198cb5cd7d5eb7af8bae830d4