build: synchronise Makefile.am with lolcore.vcxproj.

src/Makefile.am

@@ -81,10 +81,7 @@ liblolcore_sources = \
     gpu/framebuffer.cpp gpu/texture.cpp gpu/renderer.cpp \
     gpu/rendercontext.cpp \
     \
-    input/input.cpp input/input.h \
-    input/keyboard.cpp input/keyboard.h \
-    input/stick.cpp input/stick.h \
-    input/inputdevice.cpp input/inputdevice.h input/inputdevice_internal.h \
+    input/input.cpp input/input.h input/input_internal.h input/keys.h \
     input/controller.cpp input/controller.h \
     \
     gpu/defaultmaterial.lolfx \