[llvm] Aggregate errors from llvm-dwarfutil --verify (PR #79648)

[Greg Clayton via llvm-commits]

================
@@ -167,20 +167,61 @@ bool DWARFVerifier::verifyUnitHeader(const DWARFDataExtractor DebugInfoData,
   if (!ValidLength || !ValidVersion || !ValidAddrSize || !ValidAbbrevOffset ||
       !ValidType) {
     Success = false;
-    error() << format("Units[%d] - start offset: 0x%08" PRIx64 " \n", UnitIndex,
-                      OffsetStart);
+    bool headerShown = false;
     if (!ValidLength)
-      note() << "The length for this unit is too "
-                "large for the .debug_info provided.\n";
+      ErrorCategory.Report(
+          "Unit Header Length: Unit too large for .debug_info provided", [&]() {
+            if (!headerShown) {
+              error() << format("Units[%d] - start offset: 0x%08" PRIx64 " \n",
+                                UnitIndex, OffsetStart);
+              headerShown = true;
+            }
----------------
clayborg wrote:

Make this a lambda outside of each report that uses a local bool to control if it gets displayed?
```
bool headerShown = false;
auto printHeaderOnce = [&]() {
  if (!headerShown) {
    error() << format("Units[%d] - start offset: 0x%08" PRIx64 " \n", UnitIndex, OffsetStart);
    headerShown = true;
  }
};
```
Then this code becomes:
```
printHeaderOnce();
```

https://github.com/llvm/llvm-project/pull/79648