clk: qcom: Add Global Clock controller (GCC) driver for SC7280

Add support for the global clock controller found on SC7280
based devices. This should allow most non-multimedia device
drivers to probe and control their clocks.

Signed-off-by: Taniya Das <tdas@codeaurora.org>
Link: https://lore.kernel.org/r/1612981579-17391-3-git-send-email-tdas@codeaurora.org
Signed-off-by: Stephen Boyd <sboyd@kernel.org>