[llvm] [LoongArch] Precommit a test for smul with overflow (NFC) (PR #73212)

[Lu Weining via llvm-commits]

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@@ -0,0 +1,118 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc -mtriple=loongarch32 < %s | FileCheck %s --check-prefix=LA32
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SixWeining wrote:

The canonicalize usage is `--mtriple=<string>`.

https://github.com/llvm/llvm-project/pull/73212