drm/i915/uapi: expose GTT alignment

On some platforms we potentially have different alignment restrictions
depending on the memory type. We also now have different alignment
restrictions for the same region across different kernel versions.
Extend the region query to return the minimum required GTT alignment.

Testcase: igt@gem_create@create-ext-placement-alignment
Testcase: igt@i915_query@query-regions-sanity-check
Suggested-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Michal Mrozek <michal.mrozek@intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Stuart Summers <stuart.summers@intel.com>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Yang A Shi <yang.a.shi@intel.com>
Cc: Nirmoy Das <nirmoy.das@intel.com>
Cc: Niranjana Vishwanathapura <niranjana.vishwanathapura@intel.com>
Reviewed-by: Nirmoy Das <nirmoy.das@intel.com>
Acked-by: Jordan Justen <jordan.l.justen@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221004114915.221708-2-matthew.auld@intel.com