[clang] [clang] Better bitfield access units (PR #65742)

[YunQiang Su via cfe-commits]

wzssyqa wrote:

> `-mno-unalgined-access` has been added since clang17: https://reviews.llvm.org/D149946

This option is for LoongArch instead of MIPSr6.

https://github.com/llvm/llvm-project/pull/65742