drm/msm/dsi: inline msm_dsi_phy_set_src_pll

The src_truthtable config is not used for some of phys, which use other
means of configuring the master/slave usecases. Inline this function
with the goal of removing src_pll_id argument in the next commit.

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Tested-by: Stephen Boyd <swboyd@chromium.org> # on sc7180 lazor
Reviewed-by: Abhinav Kumar <abhinavk@codeaurora.org>
Link: https://lore.kernel.org/r/20210331105735.3690009-24-dmitry.baryshkov@linaro.org
Signed-off-by: Rob Clark <robdclark@chromium.org>