[llvm] [CodeGen][LoongArch] Set SINT_TO_FP/UINT_TO_FP to legal for vector types (PR #78924)

[Lu Weining via llvm-commits]

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@@ -0,0 +1,28 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 3
+; RUN: llc --mtriple=loongarch64 --mattr=+lasx < %s | FileCheck %s
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SixWeining wrote:

`+lsx` is sufficient.

https://github.com/llvm/llvm-project/pull/78924