soc: qcom: Introduce Protection Domain Restart helpers

soc: qcom: Introduce Protection Domain Restart helpers

Qualcomm SoCs (starting with MSM8998) allow for multiple protection domains
to run on the same Q6 sub-system. This allows for services like ATH10K WLAN
FW to have their own separate address space and crash/recover without
disrupting the modem and other PDs running on the same sub-system. The PDR
helpers introduces an abstraction that allows for tracking/controlling the
life cycle of protection domains running on various Q6 sub-systems.

Signed-off-by: Sibi Sankar <sibis@codeaurora.org>
Link: https://lore.kernel.org/r/20200312120842.21991-2-sibis@codeaurora.org
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>