[clang] [clang-tools-extra] [llvm] [clang] Introduce diagnostics suppression mappings (PR #112517)

[Boaz Brickner via llvm-commits]

================
@@ -108,6 +108,9 @@ class DiagnosticOptions : public RefCountedBase<DiagnosticOptions>{
   /// The file to serialize diagnostics to (non-appending).
   std::string DiagnosticSerializationFile;
 
+  /// File that defines diagnostic suppression mappings.
----------------
bricknerb wrote:

Clarify this is a filename or a full file path.

https://github.com/llvm/llvm-project/pull/112517