[llvm] Gsymutil aggregation similar to DwarfDump --verify (PR #81154)

[Greg Clayton via llvm-commits]

================
@@ -15,8 +15,8 @@
 
 ## WARNING-QUIET: Input file: {{.*\.yaml\.tmp}}
 ## WARNING-QUIET: Output file (x86_64): {{.*\.yaml\.tmp\.gsym}}
-## WARNING-QUIET: warning: Unable to retrieve DWO .debug_info section for some object files. (Remove the --quiet flag for full output)
 ## WARNING-QUIET: Pruned 0 functions, ended with 10 total
+## WARNING-QUIET: warning: Unable to retrieve DWO .debug_info section for some object files. (Remove the --quiet flag for full output)
----------------
clayborg wrote:

If this is output is non deterministic, like some stuff goes to STDERR and some stuff goes to STDOUT, you should add "-DAG" to your lines. So this will always work even if things come out in a different order:
```
## WARNING-QUIET-DAG: Pruned 0 functions, ended with 10 total
## WARNING-QUIET-DAG: warning: Unable to retrieve DWO .debug_info section for some object files. (Remove the --quiet flag for full output)
```

https://github.com/llvm/llvm-project/pull/81154