Merge commit f800c1f3b207 from llvm-project (by Arthur Eubanks):

[PEI] Don't zero out noreg operands

A tail call may have $noreg operands.

Fixes a crash.

Reviewed By: xgupta

Differential Revision: https://reviews.llvm.org/D156485

This should fix an assertion failure building qemu, specifically those
parts using -fzero-call-used-regs.

Reported by: Daniel Berrangé <dan-freebsd@berrange.com>
PR: 277474
MFC after: 3 days