drm/amd: Propagate failures in dc_set_power_state()

During the suspend process dc_set_power_state() will use kzalloc
to allocate memory, but this potentially fails with memory pressure.
If it fails, the suspend should be aborted.

Link: https://gitlab.freedesktop.org/drm/amd/-/issues/2362


Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Cc: Harry.Wentland@amd.com
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>