clk: qcom: Add display clock controller driver for SM8150 and SM8250

Add support for the display clock controller found on SM8150 and SM8250.

Signed-off-by: Jonathan Marek <jonathan@marek.ca>
Tested-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org> (SM8250)
Link: https://lore.kernel.org/r/20200927190653.13876-3-jonathan@marek.ca


Signed-off-by: Stephen Boyd <sboyd@kernel.org>