drm/msm/dsi: move ioremaps to dsi_phy_driver_probe

All PHY drivers would map dsi_pll area. Some PHY drivers would also
map dsi_phy area again (a leftover from old PHY/PLL separation). Move
all ioremaps to the common dsi_phy driver code and drop individual
ioremapped areas from PHY drivers.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Abhinav Kumar <abhinavk@codeaurora.org>
Tested-by: Stephen Boyd <swboyd@chromium.org> # on sc7180 lazor
Link: https://lore.kernel.org/r/20210331105735.3690009-21-dmitry.baryshkov@linaro.org
Signed-off-by: Rob Clark <robdclark@chromium.org>