[Polly] Add TargetTransformInfo to ScopPass standard analysis results.

TargetTransformInfo is required by IslScheduleOptimizer, as ScopPass.
Unfortunately it is not possible to get arbitrary larger-unit analyses
in for as ScopPass. Loop passes also already use TargetTransformInfo as
LoopStandardAnalysisResults, hence wei might expect it to be available
to Scop passes as well.