Revert redundant changes to tests

Author: gargaroff

llvm/test/CodeGen/AMDGPU/early-tailduplicator-nophis.mir

@@ -2,13 +2,11 @@
 # RUN: llc -mtriple=amdgcn-amd-amdhsa -mcpu=gfx900 -run-pass=early-tailduplication -verify-machineinstrs -o - %s | FileCheck %s
 
  # There are no phis in this testcase. Early tail duplication introduces them,
- # so the NoPHIs property needs to be set explicitly to false to avoid verifier
- # errors
+ # so the NoPHIs property needs to be cleared to avoid verifier errors
 
 ---
 name:           tail_duplicate_nophis
 tracksRegLiveness: true
-noPhis: false
 body:             |
   ; CHECK-LABEL: name: tail_duplicate_nophis
   ; CHECK: bb.0: