drm/xe/pf: Drop 2GiB limit of fair LMEM allocation

Since commit 678ccbf9 ("drm/xe/vram: drop 2G block
restriction") we are able to provision VFs with more than 2GiB.
Drop our temporary limit of maximum fair LMEM size that was added
just to avoid hitting -EINVAL from auto-provisioning.

Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Satyanarayana K V P <satyanarayana.k.v.p@intel.com>
Reviewed-by: Satyanarayana K V P <satyanarayana.k.v.p@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20241121175754.302-1-michal.wajdeczko@intel.com