[llvm] [RISCV] Pass the MachineInstr flag as argument to allocateStack (PR #147531)

[Sam Elliott via llvm-commits]

https://github.com/lenary commented:

This looks right, but it needs a test -- it's probably best to test this with MIR to show the MIFlags (or lack of them) on the stack adjustment.

https://github.com/llvm/llvm-project/pull/147531