src/lib.rs: make this build on big-endian aarch64.

[he32]

Do this by avoiding trying to use neon / SIMD on big-endian aarch64. Neon intrinsics are problematical on big-endian targets, ref. rust-lang/stdarch#1484

[llogiq]

Thank you!

[workingjubilee]

Please fix this by fixing the intrinsics upstream. Fixing this in every single crate is not less effort than fixing it in stdarch: rust-lang/stdarch#1484 (comment)

[he32]

Please fix this by fixing the intrinsics upstream. Fixing this in every single crate is not less effort than fixing it in stdarch: rust-lang/stdarch#1484 (comment)

Fixing the intrinsics upstream would of course be beneficial. However, I'll claim that if it was easy or little effort, that it would already be done, but that has not happened. If someone is waiting for me to fix that they are seriously over-estimating my abilities in this area. I currently appear unable to find the actual connecting tissue between library/stdarch/crates/core_arch/src/aarch64/neon/mod.rs and LLVM, and also to correlate that mod.rs with arm_neon.h from clang (which appears to be generated), and things are not lining up (names of operations don't match).

[workingjubilee]

Fixing the intrinsics upstream would of course be beneficial. However, I'll claim that if it was easy or little effort, that it would already be done, but that has not happened.

There are many things where it is fairly easy to do after a few minutes of focused effort, so I generally am skeptical of that notion. However you have taken a look, and provided feedback. That is good to know. Thank you.