[llvm] [LoopInterchange] Don't consider loops with BTC=0 (PR #167113)

[Ryotaro Kasuga via llvm-commits]

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@@ -46,6 +46,7 @@
 #include "llvm/Transforms/Utils/Local.h"
 #include "llvm/Transforms/Utils/LoopUtils.h"
 #include <cassert>
+#include <map>
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kasuga-fj wrote:

```suggestion
```
Maybe unnecessary?

https://github.com/llvm/llvm-project/pull/167113