Auto merge of #89541 - workingjubilee:abbrev-shufvec-t, r=Mark-Simulacrum

Auto merge of #89541 - workingjubilee:abbrev-shufvec-t, r=Mark-Simulacrum

Cleanup src/test/ui/{simd,simd-intrinsic}

Initial motivation was to simplify a huge macro expansion using a tuple, since we can just use an array in `#[repr(simd)]` now for the same result. But also, several tests were going unnoticed during development of SIMD intrinsics because people kept looking in the wrong directory, and many are basically run-pass vs. build-fail versions of the same tests, so let's keep them close together and simplify their names, so they're easier to sift through.