drm/amdgpu/pm: enable vcn busy sysfs for additional GC 11.x

Make it visible for the all GC 11.x chips that support it.

Reviewed-by: Lijo Lazar <lijo.lazar@amd.com>
Reviewed-by: Kenneth Feng <kenneth.feng@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>