Refactor isc__nm_socket_freebind() to take fd and sa_family as args

The isc__nm_socket_freebind() has been refactored to match other
isc__nm_socket_...() helper functions and take uv_os_fd_t and
sa_family_t as function arguments.

lib/isc/netmgr/netmgr-int.h

@@ -834,7 +834,7 @@ isc__nm_decstats(isc_nm_t *mgr, isc_statscounter_t counterid);
  */
 
 isc_result_t
-isc__nm_socket_freebind(const uv_handle_t *handle);
+isc__nm_socket_freebind(uv_os_fd_t fd, sa_family_t sa_family);
 /*%<
  * Set the IP_FREEBIND (or equivalent) socket option on the uv_handle
  */