[clang] [llvm] [RISCV] Update Zvzip support to v0.3 (PR #210603)

[Pengcheng Wang via cfe-commits]

================
@@ -5379,14 +5360,36 @@ static SDValue getSingleShuffleSrc(MVT VT, SDValue V1, SDValue V2) {
   return SDValue();
 }
 
-static bool isLegalVTForZvzipOperand(MVT VT, const RISCVSubtarget &Subtarget) {
+static unsigned getLMULOctuple(MVT ContainerVT) {
+  assert(ContainerVT.isScalableVector() && "Expected scalable vector type");
+  unsigned MinSize = ContainerVT.getSizeInBits().getKnownMinValue();
+  if (ContainerVT.getVectorElementType() == MVT::i1)
----------------
wangpc-pp wrote:

Zvzip can't shuffle mask vectors so I think we won't hit here?

https://github.com/llvm/llvm-project/pull/210603