[llvm] [AArch64][llvm] Redefine some insns as an alias of `SYS` (PR #187004)

[via llvm-commits]

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@@ -1,4 +1,8 @@
 ; RUN: llvm-mc -triple arm64-apple-darwin -mattr=neon -output-asm-variant=1 -show-encoding -print-imm-hex < %s | FileCheck %s
+; RUN: llvm-mc -triple arm64-apple-darwin -mattr=neon,+ite -filetype=obj < %s | llvm-objdump -d --mattr=+ite --no-print-imm-hex - | FileCheck %s --check-prefix=CHECK-ITE
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Lukacma wrote:

we don't have any negative tests despite the new runlines. We should add them.

https://github.com/llvm/llvm-project/pull/187004