firmware: qcom_scm: Introduce SCM calls to access LMh

Introduce SCM calls to access/configure limits management hardware(LMH).

Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Thara Gopinath <thara.gopinath@linaro.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20210809191605.3742979-2-thara.gopinath@linaro.org