We now use the same notifier lock for SVM and userptr, with that we can
combine xe_pt_userptr_pre_commit and xe_pt_svm_pre_commit.

Suggested-by: Matthew Brost <matthew.brost@intel.com>
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>