package/supertuxkart: remove libglu dependency

package/supertuxkart: remove libglu dependency

"The inclusion of GLU is historical. [...] It's not needed for GLEW to
 build or run, but it's opt-out that reason. I'd recommend using
 -DGLEW_NO_GLU since GLU is rarely seen in modern codebases nowadays."
https://github.com/nigels-com/glew/issues/192#issuecomment-411641657

Supertuxkart already uses -DGLEW_NO_GLU:
https://github.com/supertuxkart/stk-code/blob/master/CMakeLists.txt#L224

This patch only removes the dependency to libglu and depends on the
previous patch of this series which removes glu from glew.pc.

Signed-off-by: Bernd Kuhls <bernd.kuhls@t-online.de>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>