TUN-4597: Add a QUIC server skeleton

- Added a QUIC server to accept streams
- Unit test for this server also tests ALPN
- Temporary echo capability for HTTP ConnectionType

vendor/golang.org/x/net/internal/socket/sys.go

@@ -9,13 +9,8 @@ import (
 	"unsafe"
 )
 
-var (
-	// NativeEndian is the machine native endian implementation of
-	// ByteOrder.
-	NativeEndian binary.ByteOrder
-
-	kernelAlign int
-)
+// NativeEndian is the machine native endian implementation of ByteOrder.
+var NativeEndian binary.ByteOrder
 
 func init() {
 	i := uint32(1)
@@ -25,9 +20,4 @@ func init() {
 	} else {
 		NativeEndian = binary.BigEndian
 	}
-	kernelAlign = probeProtocolStack()
-}
-
-func roundup(l int) int {
-	return (l + kernelAlign - 1) &^ (kernelAlign - 1)
 }