drm/xe/vf: Do not disable VF migration on ATS-M

drm/xe/vf: Do not disable VF migration on ATS-M

Our current support for the VF migration depends on the availability
of the MEMIRQ rather than specific graphics version 20.

Relax our early migration support checks to allow also use some older
platforms like ATS-M for experiments and testing.

Do not allow ADL, as supporting VF migration through MMIO interrupts
would require additional changes in order to achieve reliability.

Reviewed-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Signed-off-by: Tomasz Lis <tomasz.lis@intel.com>
Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Link: https://lore.kernel.org/r/20251021224817.1593817-5-tomasz.lis@intel.com