[llvm] [AMDGPU][llvm-split] Fix another division by zero (PR #104421)

[Fraser Cormack via llvm-commits]

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@@ -0,0 +1,12 @@
+; RUN: llvm-split -o %t %s -j 2 -mtriple amdgcn-amd-amdhsa --debug
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frasercrmck wrote:

Ach, sorry about that!

https://github.com/llvm/llvm-project/pull/104421