Fix runtime vscale assertion in SVE

[stevesuzuki-arm]

Fix the issue that runtime vscale assert never failed whatever vector_bits is set in Target because llvm compiler asserts llvm.vscale value at compile-time and optimize away the runtime call if the function has the attribute of vscale_range(n,m) where n==m.

[zvookin]

Approve pending spelling errors. Thank you for the fix. Seems an obvious thing in retrospect, but such is the issue with not having hardware or a good sim environment to test on.

By way of code review, I'm wondering if we should favor having the intrinsic code in a .ll file aded to the runtime rather than generating it in CodeGen_LLVM. Perhaps a question for @abadams or @alexreinking.

[stevesuzuki-arm]

if we should favor having the intrinsic code in a .ll file aded to the runtime rather than generating it in CodeGen_LLVM. Perhaps a question for @abadams or @alexreinking.

I had added it to aarch64.ll, but I realized the intrinsic itself is not specific to ARM. And I couldn't find a good existing .ll file.