isl_map_simplify.c: uset_gist_full: drop unused variable
isl_map_simplify.c: uset_gist_full: drop unused variable

This was missing from 88d9f9f (isl_map_simplify.c: uset_gist_full:
negate constraint in copy, Sat Jun 20 17:30:19 2015 +0200).

Signed-off-by: Sven Verdoolaege <e5350bbed4977f5eb8ae1dc6abd9ae59d21ace75@kotnet.org>

Meinersbur/isl,PollyLabs/isl,Meinersbur/isl,inducer/isl-mirror,Meinersbur/isl,PollyLabs/isl,tobig/isl,PollyLabs/isl,inducer/isl-mirror,nicolasvasilache/isl,tobig/isl,inducer/isl-mirror,nicolasvasilache/isl,inducer/isl-mirror,nicolasvasilache/isl,tobig/isl,PollyLabs/isl,nicolasvasilache/isl,inducer/isl-mirror,PollyLabs/isl,Meinersbur/isl,nicolasvasilache/isl,tobig/isl