[clang] [llvm] [RISCV] Mark {vl, vtype} as clobber in inline assembly (PR #128636)

[Pengcheng Wang via cfe-commits]

wangpc-pp wrote:

> > I am not familiar with the target attribute implementation, can we get the list of function features here and add the clobbers at:
> > https://github.com/llvm/llvm-project/blob/6d93280aabc2fd132f54e5aa615d25abeadabe7b/clang/lib/CodeGen/CGStmt.cpp#L3087-L3093
> > 
> > cc @topperc @4vtomat
> 
> I'm not sure. But I don't understand why we need to check for Zve32x at all?

Just see the previous discussion, it is weird to add vector CSRs to clobbers if no vector support.

https://github.com/llvm/llvm-project/pull/128636