Put SCTP Zero Checksum behind SettingEngine

Old versions of Pion break against it

settingengine.go

@@ -75,6 +75,7 @@ type SettingEngine struct {
 	}
 	sctp struct {
 		maxReceiveBufferSize uint32
+		enableZeroChecksum   bool
 	}
 	sdpMediaLevelFingerprints                 bool
 	answeringDTLSRole                         DTLSRole
@@ -434,3 +435,10 @@ func (e *SettingEngine) SetDTLSKeyLogWriter(writer io.Writer) {
 func (e *SettingEngine) SetSCTPMaxReceiveBufferSize(maxReceiveBufferSize uint32) {
 	e.sctp.maxReceiveBufferSize = maxReceiveBufferSize
 }
+
+// SetSCTPZeroChecksum enables the zero checksum feature in SCTP.
+// This removes the need to checksum every incoming/outgoing packet and will reduce
+// latency and CPU usage. This feature is not backwards compatible so is disabled by default
+func (e *SettingEngine) EnableSCTPZeroChecksum(isEnabled bool) {
+	e.sctp.enableZeroChecksum = isEnabled
+}