ARM: dts: msm: Remove GPU_CC_AHB_CLK from list for SDM670

GPU AHB clock is automatically controlled by CX head switch in HW.
Remove it from GPU driver controlled clock list.

Change-Id: I36809754d8c7f465eb3fc8b405d85ccb507ec000
Signed-off-by: Kyle Piefer <kpiefer@codeaurora.org>