Log Message:
glu: Update to 9.0.1

Changes:

Amarnath Valluri (1):
     libutils/mipmap.c: Fixed possible memory leak

John Hein (1):
     pkgconfig: Include -I path for glu itself

Krzysztof Kosiński (1):
     Remove all uses of the register keyword.

Matt Turner (4):
     Add -D(N)DEBUG to CFLAGS dependent on --enable-debug
     libutil: Include stddef.h for NULL
     Switch from bz2 to xz
     glu 9.0.1

Mike Gorchak (1):
     glu: initialize PriorityQ::order field to NULL in pqNewPriorityQ()