[llvm] [NewPM] Port ImplicitNullChecks to the new pass manager (PR #216965)

[Bill Wendling via llvm-commits]

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@@ -76,7 +77,7 @@ STATISTIC(NumImplicitNullChecks,
 
 namespace {
 
-class ImplicitNullChecks : public MachineFunctionPass {
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bwendling wrote:

Done.

https://github.com/llvm/llvm-project/pull/216965