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

[Ulrich Weigand via llvm-commits]

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@@ -407,6 +407,12 @@
 # CHECK: msgrkc %r7, %r8, %r9
 0xb9 0xed 0x90 0x78
 
+# CHECK: ppno %r0, %r2
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uweigand wrote:

This is already tested in insns-z13.txt, why add it again in insns-z14?

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