drm/radeon/kms: fix fans after resume

On pre-R600 asics, the SpeedFanControl table is not
executed as part of ASIC_Init as it is on newer asics.

Fixes:
https://bugzilla.kernel.org/show_bug.cgi?id=29412



Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>