Update Makefile

src/Makefile

@@ -15,7 +15,7 @@
 #  Many thanks to Milan Nikolic (@gen2brain) for implementing Android platform pipeline.
 #  Many thanks to Emanuele Petriglia for his contribution on GNU/Linux pipeline.
 #
-#  Copyright (c) 2014-2019 Ramon Santamaria (@raysan5)
+#  Copyright (c) 2014-2021 Ramon Santamaria (@raysan5)
 #
 #  This software is provided "as-is", without any express or implied warranty.
 #  In no event will the authors be held liable for any damages arising from