[llvm] llvm-reduce: Don't print verifier failed machine functions (PR #109673)

[Matt Arsenault via llvm-commits]

arsenm wrote:

> I noticed that if I run llc now, some input that previously failed in the
> 
> ```
> MBB->getParent()->verify();

This needs to pass in the output stream to the verify call, the default is now no output 

> ```
> 
> calls in `LiveRangeCalc::findReachingDefs` and then caused nice verifier printouts now just result in `LLVM ERROR: Found 1 machine code errors.` Before I got the full output like
> 

I'm actually trying to remove all the fatal errors from LiveRangeCalc but not sure when I'll finish it 

https://github.com/llvm/llvm-project/pull/109673