[llvm] [AARCH64] Add assembly/disassembly for FMMLA instructions (PR #113313)

[via llvm-commits]

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@@ -19,3 +19,17 @@ rax1 z0.d, z0.d, z0.d
 .arch_extension sve2-bitperm
 bgrp z21.s, z10.s, z21.s
 // CHECK: bgrp z21.s, z10.s, z21.s
+
+.arch_extension sve2
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SpencerAbson wrote:

We could omit the `.arch_extension sve2` from the tests below, it follows from line 3.

https://github.com/llvm/llvm-project/pull/113313