soc: qcom: rpmpd: Add support to set rpmpd state to max

rpmpd max state varies across SoCs and SoC families, add support
in the driver to make it SoC/SoC family specific

Reviewed-by: Jeffrey Hugo <jhugo@codeaurora.org>
Reviewed-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sibi Sankar <sibis@codeaurora.org>
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Andy Gross <agross@kernel.org>