[ISLNodeBuilder] Materialize Fortran array sizes of arrays without memory accesses.

 In Polly, we specifically add a paramter to represent the outermost dimension
 size of fortran arrays. We do this because this information is statically
 available from the fortran metadata generated by dragonegg.
 However, we were only materializing these parameters (meaning, creating an
 llvm::Value to back the isl_id) from *memory accesses*. This is wrong,
 we should materialize parameters from *scop array info*.

 It is wrong because if there is a case where we detect 2 fortran arrays,
 but only one of them is accessed, we may not materialize the other array's
 dimensions at all.

 This is incorrect. We fix this by looping over all
 `polly::ScopArrayInfo` in a scop, rather that just all `polly::MemoryAccess`.

 Differential Revision: https://reviews.llvm.org/D37379

llvm-svn: 312350