[llvm] [SandboxIR][NFC] Fixes for LoadInst::create functions (PR #100955)

[via llvm-commits]

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@@ -774,13 +773,36 @@ define void @foo(ptr %arg0, ptr %arg1) {
   EXPECT_EQ(NewLd->getName(), "NewLd");
 
   sandboxir::LoadInst *NewVLd =
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vporpo wrote:

nit: Let's make this consistent with the other tests by adding a comment like: `//  Check create(InsertBefore, IsVolatile=true`)

https://github.com/llvm/llvm-project/pull/100955