tools: Fix lodviewer compilation for Windows
tools: Fix lodviewer compilation for Windows

GLFW3.h has to be included before gl.h because gl.h doesn't work as a
standalone include - needs windows.h :-/

Since GLFW3.h includes gl.h by itself we can just remove the redundant
include.

zeux/meshoptimizer,zeux/meshoptimizer,zeux/meshoptimizer