glu: Fix GLU for new libGL provided by Mesa
glu: Fix GLU for new libGL provided by Mesa

* Remove glapi hacks

miqlas/haikuports,haikuports/haikuports,moochris/haikuports,nielx/haikuports,Begasus/haikuports,koletzky/haikuports,Begasus/haikuports,miqlas/haikuports,koletzky/haikuports,moochris/haikuports,haikuports/haikuports,haikuports/haikuports,Begasus/haikuports,haikuports/haikuports,Begasus/haikuports,Begasus/haikuports,miqlas/haikuports,nielx/haikuports,nielx/haikuports,moochris/haikuports,haikuports/haikuports,koletzky/haikuports