[llvm] [MIRPrinter] Don't print space when there is no successor (PR #80143)

[Quentin Dian via llvm-commits]

DianQK wrote:

> > > > This also prints two line breaks, and I think we can delete one.
> > > 
> > > 
> > > But you haven't done that in this patch, right?
> > 
> > 
> > This breaks many test cases. If appropriate, I'll create another PR.
> 
> I find it a little confusing to even mention it in the commit message, if the commit does not change it.

I'll update the commit message when I merge it.

(Lest I forget, I've updated the PR description.)

https://github.com/llvm/llvm-project/pull/80143