hostapd: Add possibility to send debug messages to syslog
We can only send module specific messages to syslog and not debug
messages printed with wpa_printf. Add an extra command line parameter
'-s' to allow it. The feature is enabled with compile flag
CONFIG_DEBUG_SYSLOG as for wpa_supplicant and behaves in the same manner
as the wpa_supplicant -s command line argument.
Signed-off-by: Wojciech Dubowik <Wojciech.Dubowik@neratec.com>