drm/amd/display: Engage PSR synchronously

[Why & How]
The intended use is to force PSR into active state and ignore all
events until explicit EXIT.
A new event force_static is added to power module. It is then sent
to FW.

Signed-off-by: Krunoslav Kovac <Krunoslav.Kovac@amd.com>
Acked-by: Bindu Ramamurthy <bindu.r@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>