clk: qcom: msm8996-cpu: Convert secondary muxes to clk_regmap_mux

There is nothing special about the secondary muxes, unlike the
primary muxes which need some extra logic to handle ACD and
switching between primary PLL and secondary mux sources. Turn
them into clk_regmap_mux and rename cpu_clk_msm8996_mux into
cpu_clk_msm8996_pmux to make it specific to primary muxes.

Signed-off-by: Yassine Oudjana <y.oudjana@protonmail.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20220621160621.24415-5-y.oudjana@protonmail.com