[LV] Move InterleaveGroup and InterleavedAccessInfo to VectorUtils.h (NFC)

Move the 2 classes out of LoopVectorize.cpp to make it easier to re-use
them for VPlan outside LoopVectorize.cpp

Reviewers: Ayal, mssimpso, rengolin, dcaballe, mkuper, hsaito, hfinkel, xbolva00

Reviewed By: rengolin, xbolva00

Differential Revision: https://reviews.llvm.org/D49488



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@342027 91177308-0d34-0410-b5e6-96231b3b80d8
5 files changed