Add missing source files in server Makefile

All classes were still built, but make was not able to detect changes on
missing files.

server/Makefile

@@ -25,6 +25,9 @@ SRC := com/genymobile/scrcpy/ScrCpyServer.java \
 	com/genymobile/scrcpy/DesktopConnection.java \
 	com/genymobile/scrcpy/Device.java \
 	com/genymobile/scrcpy/EventController.java \
+	com/genymobile/scrcpy/Ln.java \
+	com/genymobile/scrcpy/Point.java \
+	com/genymobile/scrcpy/RawPoint.java \
 	com/genymobile/scrcpy/ScreenInfo.java \
 	com/genymobile/scrcpy/ScreenStreamer.java \
 	com/genymobile/scrcpy/ScreenStreamerSession.java \