drm/xe: Fix splat during error dump

Allow xe_bo_addr without lock to print debug information, such
as from xe_analyze_vm.

Signed-off-by: Francois Dugast <francois.dugast@intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>