drm/xe: Add missing '@' prefix to kernel-doc member tags

drm/xe: Add missing '@' prefix to kernel-doc member tags

Add the required '@' prefix to member documentation tags that were
missing it. Without the prefix, kernel-doc does not associate the
comment with the struct member.

- xe_guc_ct_types.h: snapshot_ct -> @snapshot_ct,
  snapshot_log -> @snapshot_log
- xe_pagefault_types.h: consumer.reserved -> @consumer.reserved
- xe_pt_types.h: addr -> @addr

Assisted-by: GitHub Copilot:claude-sonnet-4.6
Reviewed-by: Brian Nguyen <brian3.nguyen@intel.com>
Link: https://patch.msgid.link/20260414225457.3687449-3-shuicheng.lin@intel.com
Signed-off-by: Shuicheng Lin <shuicheng.lin@intel.com>