Applied the Sangoma patch to FS version 1.2 in order to port to FS v1.6+

Sourced from:
http://gitlab.sangoma.com/projects/CORE/repos/freetdm/browse/public_freeswitch/sangoma-FS-1.2.patch

libs/apr/network_io/unix/sockopt.c

@@ -344,6 +344,16 @@ apr_status_t apr_socket_opt_get(apr_socket_t *sock,
 }
 
 
+int apr_socket_fd_get(apr_socket_t *sock)
+{
+	if (sock) {
+		return sock->socketdes;
+	} else {
+		return 0;
+	}
+}
+
+
 apr_status_t apr_socket_atmark(apr_socket_t *sock, int *atmark)
 {
 #ifndef BEOS_R5