drm/amd/amdgpu: simplify pa_sc_tile_steering_override check

Use ">= CHIP_SIENNA_CICHLID" to replace per asic check

Signed-off-by: Chengming Gui <Jack.Gui@amd.com>
Reviewed-by: Hawking.Zhang <Hawking.Zhang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>