ARM: dts: msm: remove mem_acc regulators from APC CPR regulators on msm8992

The latest hardware documentation states that memory accelerator
settings should be the same for all corners on both A53 and A57
clusters. The hardware default MEM ACC configuration already
provides the correct settings so there is nothing for software
to manage. Thus, remove the mem_acc regulators from APC CPR
regulators and keep them disabled in the device tree.

Change-Id: Ie3d12eb0f338dd14e1278de28c6cd9d2ef5afa42
Signed-off-by: Ke Liu <keliu@codeaurora.org>
Signed-off-by: Subbaraman Narayanamurthy <subbaram@codeaurora.org>