If AMDGPU supports SI, add a module parameter to control SI
support in radeon. It's on by default in radeon, while it will be
off by default in AMDGPU as long as SI support is experimental.
Signed-off-by: NFelix Kuehling <Felix.Kuehling@amd.com>
Reviewed-by: NChristian König <christian.koenig@amd.com>
Acked-by: NMichel Dänzer <michel.daenzer@amd.com>