firmware: qcom_scm: Add SM6375 compatible

While it was introduced in bindings, requiring a core clock, and added
into the DT, this compatible was apparently forgotten about on the driver
side of things. Fix it.

Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20230307012247.3655547-1-konrad.dybcio@linaro.org