add presence-probe-on-register sofia param to send a probe on register instead of presence to deal with some broken phones and add some general improvements to allow multi homed presence

src/mod/endpoints/mod_sofia/mod_sofia.h

@@ -224,6 +224,7 @@ typedef enum {
 	PFLAG_IN_DIALOG_CHAT,
 	PFLAG_DEL_SUBS_ON_REG,
 	PFLAG_IGNORE_183NOSDP,
+	PFLAG_PRESENCE_PROBE_ON_REGISTER,
 	/* No new flags below this line */
 	PFLAG_MAX
 } PFLAGS;