add checksum offload support to NIC

generators/example/src/main/scala/ConfigMixins.scala

@@ -220,7 +220,8 @@ class WithIceNIC(inBufFlits: Int = 1800, usePauser: Boolean = false)
     extends Config((site, here, up) => {
   case NICKey => NICConfig(
     inBufFlits = inBufFlits,
-    usePauser = usePauser)
+    usePauser = usePauser,
+    checksumOffload = true)
 })
 
 class WithLoopbackNICTop extends Config((site, here, up) => {

generators/firechip/src/main/scala/TargetConfigs.scala

@@ -52,7 +52,8 @@ class WithBlockDevice extends Config(new testchipip.WithBlockDevice)
 class WithNICKey extends Config((site, here, up) => {
   case NICKey => NICConfig(
     inBufFlits = 8192,
-    ctrlQueueDepth = 64)
+    ctrlQueueDepth = 64,
+    checksumOffload = true)
 })
 
 class WithRocketL2TLBs(entries: Int) extends Config((site, here, up) => {