[MLIR] Don't use SSA names directly for std.view canonicalization test

Reviewers: rriddle, nicolasvasilache

Subscribers: mehdi_amini, jpienaar, burmako, shauheen, antiagainst, arpith-jacob, mgester, lucyrfox, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D72408