device: remove version string

This is what modules are for, and Go binaries can introspect.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

main_windows.go

@@ -34,7 +34,7 @@ func main() {
 		device.LogLevelVerbose,
 		fmt.Sprintf("(%s) ", interfaceName),
 	)
-	logger.Verbosef("Starting wireguard-go version %s", device.WireGuardGoVersion)
+	logger.Verbosef("Starting wireguard-go version %s", Version)
 
 	tun, err := tun.CreateTUN(interfaceName, 0)
 	if err == nil {