drm/amdgpu/gfx: only call mes for enforce isolation if supported

This should not be called on chips without MES so check if
MES is enabled and if the cleaner shader is supported.

Fixes: 8521e3c5 ("drm/amd/amdgpu: limit single process inside MES")
Reviewed-by: Srinivasan Shanmugam <srinivasan.shanmugam@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: Shaoyun Liu <shaoyun.liu@amd.com>
Cc: Srinivasan Shanmugam <srinivasan.shanmugam@amd.com>