[libcxx] [libcxxabi] [libunwind] [NFC][libc++][libc++abi][libunwind][test] Fix/unify AIX triples used in LIT tests (PR #101196)

[Saleem Abdulrasool via cfe-commits]

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@@ -10,7 +10,7 @@
 // on AIX. Option -O3 is required so that the compiler will re-use the value
 // in the condition register instead of re-evaluating the condition expression.
 
-// REQUIRES: target=powerpc{{(64)?}}-ibm-aix
+// REQUIRES: target={{.+}}-aix{{.*}}
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compnerd wrote:

Why drop the vendor in the vendor specific directory?

https://github.com/llvm/llvm-project/pull/101196