[WebAssembly] Lower SIMD nnan setcc nodes

Summary:
Adds patterns to lower all the remaining setcc modes: lt, gt,
le, and ge. Fixes PR40912.

Reviewers: aheejin, sbc100, dschuff

Reviewed By: dschuff

Subscribers: jgravelle-google, hiraditya, sunfish, jdoerfert, llvm-commits, srj

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D59519

llvm-svn: 356431