package/freeswitch: enable mod_timerfd

Mod_timerfd uses the Linux kernel timerfd API to create and use a kernel
timer that delivers timer expire notifications via a file descriptor,
for details read

https://freeswitch.org/confluence/display/FREESWITCH/mod_timerfd
Signed-off-by: Bernd Kuhls <bernd.kuhls@t-online.de>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/freeswitch/freeswitch.mk

@@ -150,6 +150,7 @@ FREESWITCH_ENABLED_MODULES += \
 	say/mod_say_sv \
 	say/mod_say_th \
 	say/mod_say_zh \
+	timers/mod_timerfd \
 	xml_int/mod_xml_cdr \
 	xml_int/mod_xml_rpc \
 	xml_int/mod_xml_scgi