soc: qcom: stats: Add SDM845 stats config and compatible

SDM845 is a special case compared to the other platforms that use RPMh
stats, since it only has 2 stats (aosd and cxsd), while the others have
a 3rd one (ddr).

So lets add dedicated stats config and compatible for SDM845 to make the
driver aware of this num_records difference.

Signed-off-by: Abel Vesa <abel.vesa@linaro.org>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20220812101240.1869605-2-abel.vesa@linaro.org