Merge branch 'V5-6-patches' into V5-7-patches

* V5-6-patches:
  Remove the NETSNMP_DONTWAIT / NETSNMP_NOSIGNAL aliases for sendto/sendmsg flags

Conflicts:
	include/net-snmp/library/snmpUDPBaseDomain.h
	snmplib/transports/snmpDTLSUDPDomain.c
	snmplib/transports/snmpUDPBaseDomain.c