This removes { dg-final { scan-tree-dump "tiled" "graphite" } } scans
from graphite tests that pass/fail dependent on the ISL version used.
Note all scans match the actually dumped "not tiled" messages with
ISL 0.12 and not the alternative "tiled by <number>". With ISL
0.22 neither is printed because the tiling infrastructure doesn't
expect the new schedule layout (though looking at a few cases it
looks superior with more dimensions marked as permutable.
Anyway, the scans have nothing to do with interchange and just
add to testsuite noise.