[clang] [llvm] [AArch64] Add updated FEAT_SVE_B16B16 and begin replacement of 'b16b16' flag (PR #101480)

[via llvm-commits]

https://github.com/CarolineConcatto commented:

Thank you Spencer for the patch.
I believe we missed the  multi vector instructions targeting BF16.
 

https://github.com/llvm/llvm-project/pull/101480