Fix compilation issues related to SNMP.
Fix compilation issues related to SNMP.

biddyweb/flexisip,gale320/flexisip,BelledonneCommunications/flexisip,gale320/flexisip,BelledonneCommunications/flexisip,biddyweb/flexisip,biddyweb/flexisip,BelledonneCommunications/flexisip,BelledonneCommunications/flexisip,biddyweb/flexisip,gale320/flexisip,gale320/flexisip