Cleanup: Correct an own earlier commit to use an existing utility function

Didn't know this function existed, better to use it then to avoid verbosity.

source/blender/blenloader/intern/blend_validate.c

@@ -148,7 +148,7 @@ bool BLO_main_validate_libraries(Main *bmain, ReportList *reports)
         }
       }
 
-      BLI_linklist_free(names, MEM_freeN);
+      BLI_linklist_freeN(names);
     }
 
     BLO_blendhandle_close(bh);

source/blender/editors/space_file/filelist.c

@@ -2621,7 +2621,7 @@ static int filelist_readjob_list_lib(const char *root, ListBase *entries, const
     nbr_entries++;
   }
 
-  BLI_linklist_free(names, MEM_freeN);
+  BLI_linklist_freeN(names);
 
   return nbr_entries;
 }

source/blender/imbuf/intern/thumbs_blend.c

@@ -68,7 +68,7 @@ ImBuf *IMB_thumb_load_blend(const char *blen_path, const char *blen_group, const
         printf("%s: error, found %d items, %d previews\n", __func__, nnames, nprevs);
       }
       BLI_linklist_free(previews, BKE_previewimg_freefunc);
-      BLI_linklist_free(names, MEM_freeN);
+      BLI_linklist_freeN(names);
       return ima;
     }
 
@@ -93,7 +93,7 @@ ImBuf *IMB_thumb_load_blend(const char *blen_path, const char *blen_group, const
     }
 
     BLI_linklist_free(previews, BKE_previewimg_freefunc);
-    BLI_linklist_free(names, MEM_freeN);
+    BLI_linklist_freeN(names);
   }
   else {
     BlendThumbnail *data;

source/blender/python/intern/bpy_library_load.c

@@ -227,7 +227,7 @@ static PyObject *_bpy_names(BPy_Library *self, int blocktype)
       PyList_SET_ITEM(list, counter, PyUnicode_FromString((char *)l->link));
       counter++;
     }
-    BLI_linklist_free(names, MEM_freeN); /* free linklist *and* each node's data */
+    BLI_linklist_freeN(names); /* free linklist *and* each node's data */
   }
 
   return list;