[LoopUnswitch] Make DEBUG output more readable.
[LoopUnswitch] Make DEBUG output more readable.

While debugging a miscompile I realized loopunswitch doesn't
put newlines when printing the instruction being replacement.
Ending up with a single line with many instruction replaced isn't
the best for readability and/or mental sanity.

git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@301692 91177308-0d34-0410-b5e6-96231b3b80d8

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