Chore: remove unused logger

core/src/main/golang/tun/log.go

-package tun
-
-import "github.com/Dreamacro/clash/log"
-
-type logger struct{}
-
-func (l *logger) D(format string, args ...interface{}) {
-	log.Debugln(format, args...)
-}
-
-func (l *logger) I(format string, args ...interface{}) {
-	log.Infoln(format, args...)
-}
-
-func (l *logger) W(format string, args ...interface{}) {
-	log.Warnln(format, args...)
-}
-
-func (l *logger) E(format string, args ...interface{}) {
-	log.Errorln(format, args...)
-}