Coverity warnings

Remove coverity warnings CID 896127 (dotrunner.cpp) and 896849 (symbolresolver.cpp)

Author: albert-github

src/dotrunner.cpp

@@ -79,6 +79,7 @@ static void checkPngResult(const QCString &imgName)
   if (fread(data, 1, 4, f) != 4)
   {
     err("Could not read image '{}' generated by dot!\n",imgName);
+    fclose(f);
     return;
   }
 

src/symbolresolver.cpp

@@ -539,7 +539,7 @@ const Definition *SymbolResolver::Private::getResolvedSymbolRec(
         if (d->definitionType()==Definition::TypeMember)
         {
           const MemberDef *emd = dynamic_cast<const MemberDef *>(d);
-          if (emd->isEnumValue() && emd->getEnumScope() && emd->getEnumScope()->isStrong() && explicitScopePart.isEmpty())
+          if (emd && emd->isEnumValue() && emd->getEnumScope() && emd->getEnumScope()->isStrong() && explicitScopePart.isEmpty())
           {
             // skip lookup for strong enum values without explicit scope, see issue #11799
             continue;