[llvm] [z/OS] Modify regex in error message to match on z/OS. (PR #194020)

[via llvm-commits]

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@@ -18,7 +18,7 @@
 # CHECK: Command Output (stderr):
 # CHECK-NEXT: --
 # CHECK-NOT: --
-# CHECK: cat{{(_64)?(\.exe)?}}: {{(cannot open does-not-exist|.*does-not-exist.*: No such file or directory)}}
+# CHECK: cat{{(_64)?(\.exe)?}}: {{(cannot open does-not-exist|.*does-not-exist.*: .*No such file or directory)}}
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sujianIBM wrote:

Hello, I modified shtest-format.py to use both `%errc_ENOENT` and `%if`.
Would you please take a look? 
If this is OK, I will apply the same change to shtest-output-printing.
Thanks!

https://github.com/llvm/llvm-project/pull/194020