clk: qcom: add the driver for the MSM8996 APCS clocks

clk: qcom: add the driver for the MSM8996 APCS clocks

Add a simple driver handling the APCS clocks on MSM8996. For now it
supports just a single aux clock, linking GPLL0 to CPU and CBF clocks.

Note, there is little sense in registering sys_apcs_aux as a child of
gpll0. The PLL is always-on. And listing the gpll0 as a property of the
apcs would delay its probing until the GCC has been probed (while we
would like for the apcs to be probed as early as possible).

Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
[bjorn: Fixed spelling of register, per Stephen's feedback]
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20230126230319.3977109-8-dmitry.baryshkov@linaro.org