[llvm] [MIRPrinter] Don't print line break when there is no instructions (PR #80147)

[Quentin Dian via llvm-commits]

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@@ -136,9 +136,8 @@ define i32 @test_cfg_remap_multiple_preds(i32 %in) {
   ; CHECK-NEXT: {{  $}}
   ; CHECK-NEXT: bb.2.odd:
   ; CHECK-NEXT:   successors:
-  ; CHECK: {{  $}}
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DianQK wrote:

It looks like we've had this problem before.

https://github.com/llvm/llvm-project/pull/80147