soc: qcom: llcc: Add per-slice counter and common llcc slice descriptor

soc: qcom: llcc: Add per-slice counter and common llcc slice descriptor

Fix incorrect slice activation/deactivation accounting by replacing the
bitmap-based activation tracking with per-slice atomic reference counters.
This resolves mismatches that occur when multiple client drivers vote for
the same slice or when llcc_slice_getd() is called multiple times.

As part of this fix, simplify slice descriptor handling by eliminating
dynamic allocation. llcc_slice_getd() now returns a pointer to a
preallocated descriptor, removing the need for repeated allocation/free
cycles and ensuring consistent reference tracking across all users.

Signed-off-by: Unnathi Chalicheemala <unnathi.chalicheemala@oss.qualcomm.com>
Signed-off-by: Francisco Munoz Ruiz <francisco.ruiz@oss.qualcomm.com>
Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Link: https://lore.kernel.org/r/20260305-external_llcc_changes1set-v1-1-6347e52e648e@oss.qualcomm.com
Signed-off-by: Bjorn Andersson <andersson@kernel.org>