drm/amd/pm: drop unneeded thermal_controller_type check

As there is actually no direct dependence between them.

Signed-off-by: Evan Quan <evan.quan@amd.com>
Reviewed-by: Hawking Zhang <Hawking.Zhang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>