[llvm] [RISCV] Expand constant multiplication for targets without M extension (PR #137195)

[Sam Elliott via llvm-commits]

================
@@ -15447,20 +15584,23 @@ static SDValue expandMul(SDNode *N, SelectionDAG &DAG,
   if (DAG.getMachineFunction().getFunction().hasMinSize())
----------------
lenary wrote:

Given you're not changing the code, this is probably correct, and if it's not, there's an easy one-line follow-up to get a code size win for `-Os`

https://github.com/llvm/llvm-project/pull/137195