This driver purely exposes information from memory to the kernel. Let's
mark it as not having any device PM functionality, so that during
suspend we skip even trying to call a suspend function on this device.
This clears up suspend logs more than anything else, but it also shaves
a few cycles off suspend.

Cc: Konrad Dybcio <konrad.dybcio@somainline.org>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20221015004934.3930651-2-swboyd@chromium.org