remoteproc: qcom: Introduce panic handler for PAS and ADSP

Make the PAS and ADSP/CDSP remoteproc drivers implement the panic
handler that will invoke a stop to prepare the remoteprocs for post
mortem debugging.

Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Link: https://lore.kernel.org/r/20200324052904.738594-5-bjorn.andersson@linaro.org


Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>