res_mwi_external_ami: Use module version of AMI registration.

Use ast_manager_register_xml for res_mwi_external_ami manager
actions.  This ensures the module is held open while any of
the actions are being run.

ASTERISK-25117 #close
Reported by: Corey Farrell

Change-Id: Iececfdc2da498b2c32b9e09042f5f12292007ac7

res/res_mwi_external_ami.c

@@ -357,9 +357,9 @@ static int load_module(void)
 	ast_mwi_external_ref();
 
 	res = 0;
-	res |= ast_manager_register_xml_core("MWIGet", EVENT_FLAG_CALL | EVENT_FLAG_REPORTING, mwi_mailbox_get);
-	res |= ast_manager_register_xml_core("MWIDelete", EVENT_FLAG_CALL, mwi_mailbox_delete);
-	res |= ast_manager_register_xml_core("MWIUpdate", EVENT_FLAG_CALL, mwi_mailbox_update);
+	res |= ast_manager_register_xml("MWIGet", EVENT_FLAG_CALL | EVENT_FLAG_REPORTING, mwi_mailbox_get);
+	res |= ast_manager_register_xml("MWIDelete", EVENT_FLAG_CALL, mwi_mailbox_delete);
+	res |= ast_manager_register_xml("MWIUpdate", EVENT_FLAG_CALL, mwi_mailbox_update);
 	if (res) {
 		unload_module();
 		return AST_MODULE_LOAD_DECLINE;