[llvm] [readtapi] Add Merge functionality (PR #72656)

[Juergen Ributzka via llvm-commits]

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@@ -138,8 +155,22 @@ int main(int Argc, char **Argv) {
     }
   }
 
+  if (Args.hasArg(OPT_compact))
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ributzka wrote:

nit: this could be condensed into a single line. `Ctx.Compact = Args.hasArg(OPT_compact);`

https://github.com/llvm/llvm-project/pull/72656