clk: qcom: Add MSM8998 Multimedia Clock Controller (MMCC) driver

Add a driver for the multimedia clock controller found on MSM8998
based devices. This should allow most multimedia device drivers
to probe and control their clocks.

Signed-off-by: Jeffrey Hugo <jhugo@codeaurora.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lkml.kernel.org/r/1576596033-10189-1-git-send-email-jhugo@codeaurora.org


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