fnsince.pl: SDL_UnregisterApp() also arrived in 2.0.2.

build-scripts/fnsince.pl

@@ -88,6 +88,7 @@ $funcs{'SDL_Direct3D9GetAdapterIndex'} = '2.0.1';
 $funcs{'SDL_RenderGetD3D9Device'} = '2.0.1';
 
 $funcs{'SDL_RegisterApp'} = '2.0.2';
+$funcs{'SDL_UnregisterApp'} = '2.0.2';
 $funcs{'SDL_GetAssertionHandler'} = '2.0.2';
 $funcs{'SDL_GetDefaultAssertionHandler'} = '2.0.2';
 $funcs{'SDL_AtomicAdd'} = '2.0.2';