Remove unused AMDGPU_GEM_CREATE_SHADOW flag.
Userspace is never allowed to use this.
Signed-off-by: NNirmoy Das <nirmoy.das@amd.com>
Reviewed-by: NChristian König <christian.koenig@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>