gpu.c: extract_stmts: drop redundant argument
gpu.c: extract_stmts: drop redundant argument

The argument was made redundant in 6395482 (gpu.c: compute_schedule:
take domain from ppcg_scop, Tue Oct 16 20:25:37 2012 +0200).

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

nicolasvasilache/ppcg,Meinersbur/ppcg,Meinersbur/ppcg,nicolasvasilache/ppcg