OpenGL3 driver no longer builds

[kaetemi]

/home/vsts/work/1/s/nel/src/3d/dru.cpp:138:11: error: declaration of ‘static NL3D::IDriver* NL3D::CDRU::createGl3Driver()’ has a different exception specifier
 IDriver  *CDRU::createGl3Driver()
           ^~~~
In file included from /home/vsts/work/1/s/nel/src/3d/dru.cpp:25:
/home/vsts/work/1/s/nel/include/nel/3d/dru.h:171:19: note: from previous declaration ‘static NL3D::IDriver* NL3D::CDRU::createGl3Driver() throw (NL3D::EDru)’
  static IDriver  *createGl3Driver() throw(EDru);
                   ^~~~~~~~~~~~~~~

on feature/opengl3 branch

[kervala]

You can remove "throw(EDru)" since compilers deprecated it in recent C++ versions :)