Clang: Initialize errorType

Change-Id: I1a418c8cda02320c6157635755f03bdc14d28a9e
Reviewed-by: Tim Jenssen <tim.jenssen@qt.io>

src/libs/clangbackendipc/dynamicastmatcherdiagnosticmessagecontainer.h

@@ -101,7 +101,7 @@ public:
 
 private:
     V2::SourceRangeContainer sourceRange_;
-    ClangQueryDiagnosticErrorType errorType_;
+    ClangQueryDiagnosticErrorType errorType_ = ClangQueryDiagnosticErrorType::None;
     Utils::SmallStringVector arguments_;
 };