drm/msm/sde: Enable PA HSIC and six-zone feature via reg_dma

PA HSIC and six-zone features are enabled via AHB path only on
SDM845 because reg_dma version 1 doesn't have the support to
modify specific fields of the register via mask. Reg_modify
support has been added to Reg_dma version 1.1, so this change
adds the reg_dma path for PA HSIC and six-zone features.

Change-Id: I53686fde382c46803de2e7023f1b16c812db5ccc
Signed-off-by: Ping Li <pingli@codeaurora.org>