BLI_utildefines: rename pointer conversion macros

Terms get/set don't make much sense when casting values.

Name macros so the conversion is obvious,
use common prefix for easier completion.

- GET_INT_FROM_POINTER  -> POINTER_AS_INT
- SET_INT_IN_POINTER    -> POINTER_FROM_INT
- GET_UINT_FROM_POINTER -> POINTER_AS_UINT
- SET_UINT_IN_POINTER   -> POINTER_FROM_UINT

source/blender/python/intern/bpy_app_handlers.c

@@ -241,7 +241,7 @@ PyObject *BPY_app_handlers_struct(void)
 			funcstore = &funcstore_array[pos];
 			funcstore->func = bpy_app_generic_callback;
 			funcstore->alloc = 0;
-			funcstore->arg = SET_INT_IN_POINTER(pos);
+			funcstore->arg = POINTER_FROM_INT(pos);
 			BLI_callback_add(funcstore, pos);
 		}
 	}
@@ -300,7 +300,7 @@ void BPY_app_handlers_reset(const short do_all)
 /* the actual callback - not necessarily called from py */
 void bpy_app_generic_callback(struct Main *UNUSED(main), struct ID *id, void *arg)
 {
-	PyObject *cb_list = py_cb_array[GET_INT_FROM_POINTER(arg)];
+	PyObject *cb_list = py_cb_array[POINTER_AS_INT(arg)];
 	if (PyList_GET_SIZE(cb_list) > 0) {
 		PyGILState_STATE gilstate = PyGILState_Ensure();