Fix build error when WITH_XR_OPENXR not defined

source/blender/makesrna/intern/rna_xr.c

@@ -901,9 +901,13 @@ static void rna_XrSessionState_viewer_pose_rotation_get(PointerRNA *ptr, float *
 
 static void rna_XrSessionState_actionmaps_begin(CollectionPropertyIterator *iter, PointerRNA *ptr)
 {
+#  ifdef WITH_XR_OPENXR
   wmXrData *xr = rna_XrSession_wm_xr_data_get(ptr);
   ListBase *lb = WM_xr_actionmaps_get(xr->runtime);
   rna_iterator_listbase_begin(iter, lb, NULL);
+#  else
+  UNUSED_VARS(iter, ptr);
+#  endif
 }
 
 static int rna_XrSessionState_active_actionmap_get(PointerRNA *ptr)