[SVE] Eliminate calls to default-false VectorType::get() from Analysis

Reviewers: efriedma, fpetrogalli, kmclaughlin, sunfish

Reviewed By: fpetrogalli

Subscribers: tschuett, hiraditya, rkruppe, psnobl, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D80324