[MemorySSA] Update test to use NewPM (llvm#72915)

This test is the last holdout that still uses the legacy loop simplify
CFG pass. The issues originally pointed out in the test comments seem to
have been fixed now as there are no MemorySSA verification failures.

llvm/test/Analysis/MemorySSA/update-remove-dead-blocks.ll

@@ -1,8 +1,5 @@
 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
-; RUN: opt -simple-loop-unswitch -loop-reduce -loop-simplifycfg -verify-memoryssa -S %s | FileCheck %s
-
-; TODO: also run with NPM, but currently LSR does not preserve LCSSA, causing a verification failure on the test.
-;   opt -passes='loop-mssa(simple-loop-unswitch<nontrivial>,loop-reduce,simplifycfg)' -verify-memoryssa -S %s | FileCheck %s
+; RUN: opt -passes='loop-mssa(simple-loop-unswitch<nontrivial>,loop-reduce,loop-simplifycfg)' -verify-memoryssa -S %s | FileCheck %s
 
 ; Test case for PR47557.
 
@@ -18,8 +15,8 @@ define ptr @test() {
 ; CHECK-LABEL: @test(
 ; CHECK-NEXT:  entry:
 ; CHECK-NEXT:    switch i32 0, label [[ENTRY_SPLIT:%.*]] [
-; CHECK-NEXT:    i32 1, label [[FOR_BODY3SPLIT:%.*]]
-; CHECK-NEXT:    i32 2, label [[FOR_COND2_2_FOR_BODY3_CRIT_EDGE:%.*]]
+; CHECK-NEXT:      i32 1, label [[FOR_BODY3SPLIT:%.*]]
+; CHECK-NEXT:      i32 2, label [[FOR_COND2_2_FOR_BODY3_CRIT_EDGE:%.*]]
 ; CHECK-NEXT:    ]
 ; CHECK:       entry.split:
 ; CHECK-NEXT:    br label [[FOR_COND:%.*]]