[llvm] [SystemZ] Add missing (dis-)assembly tests. (PR #88498)

[Ulrich Weigand via llvm-commits]

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@@ -10656,18 +10752,6 @@
 # CHECK: lxdbr %f13, %f15
 0xb3 0x05 0x00 0xdf
 
-# CHECK: lxdr %f0, %f8
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uweigand wrote:

Why are you removing these?  That isn't mentioned in the commit message at all ...

https://github.com/llvm/llvm-project/pull/88498