[WebAssembly] Improve codegen for v128.bitselect

Add patterns selecting ((v1 ^ v2) & c) ^ v2 and ((v1 ^ v2) & ~c) ^ v2 to
v128.bitselect.

Resolves #56827.

Reviewed By: aheejin

Differential Revision: https://reviews.llvm.org/D131131

GitOrigin-RevId: b19de814add2c2d9496c0b2fcc8a47024a58e491
2 files changed