clk: qcom: Add graphics clock controller driver for SC7280

Add support for the graphics clock controller found on SC7280
based devices. This would allow graphics drivers to probe and
control their clocks.

Signed-off-by: Taniya Das <tdas@codeaurora.org>
Link: https://lore.kernel.org/r/1626189143-12957-6-git-send-email-tdas@codeaurora.org
Signed-off-by: Stephen Boyd <sboyd@kernel.org>