res_sorcery_memory_cache: Backport to 13

Gerrit is complaining of conflicts when trying to create a patch series
of all of the cherry-picked master commits, so I have instead squashed
it all into one commit.

ASTERISK-25067 #close
Reported by: Matt Jordan

Change-Id: I6dda90343fae24a75dc5beec84980024e8d61eb9

main/sorcery.c

@@ -2356,3 +2356,8 @@ int ast_sorcery_is_object_field_registered(const struct ast_sorcery_object_type
 	ao2_cleanup(object_field);
 	return res;
 }
+
+const char *ast_sorcery_get_module(const struct ast_sorcery *sorcery)
+{
+	return sorcery->module_name;
+}