clk: qcom: add msm8996 Core Bus Framework (CBF) support

Add CBF clock driver as a part of MSM8996 CPU clocks. Significantly
based on AngeloGioacchino del Regno's work at [1].

The CBF is an interconnect between two CPU clusters, setting it up
properly is required for booting the MSM8996 with all four cores
enabled.

[1] https://github.com/sonyxperiadev/kernel/blob/aosp/LE.UM.2.3.2.r1.4/drivers/clk/qcom/clk-cpu-8996.c



Co-developed-by: Konrad Dybcio <konrad.dybcio@somainline.org>
Signed-off-by: Konrad Dybcio <konrad.dybcio@somainline.org>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
[bjorn: Dropped partially uninitialized variable "ret" from cbf_clk_notifier_cb()]
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20230120061417.2623751-4-dmitry.baryshkov@linaro.org