drm/amdgpu: enable GFX-V11 userqueue support

drm/amdgpu: enable GFX-V11 userqueue support

This patch enables GFX-v11 IP support in the usermode queue base
code. It typically:
- adds a GFX_v11 specific MQD structure
- sets IP functions to create and destroy MQDs
- sets MQD objects coming from userspace

V10: introduced this spearate patch for GFX V11 enabling (Alex).
V11: Addressed review comments:
     - update the comments in GFX mqd structure informing user about using
       the INFO IOCTL for object sizes (Alex)
     - rename struct drm_amdgpu_userq_mqd_gfx_v11 to
       drm_amdgpu_userq_mqd_gfx11 (Marek)

Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Christian Koenig <christian.koenig@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Shashank Sharma <shashank.sharma@amd.com>
Signed-off-by: Arvind Yadav <arvind.yadav@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>