[clang] [CIR][Aarch64] upstream scalar & vector intrinsics (FP16) (PR #190310)

[Andrzej Warzyński via cfe-commits]

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banach-space wrote:

No need to create a new file, you can re-use https://github.com/llvm/llvm-project/blob/8d7823ea8f40cf5df1c623018bf9c0a308fa4a36/clang/test/CodeGen/AArch64/neon/fullfp16.c.

Sorry for the confusion!

Also, please remember to delete the original tests, as documented here: https://github.com/llvm/llvm-project/issues/185382#issuecomment-4022508229

[nice-to-have] Would you mind adding block comments?

https://github.com/llvm/llvm-project/pull/190310