Ref T488 Update cppcheck suppressions.

src/blackmisc/dbusserver.cpp

@@ -367,6 +367,7 @@ namespace BlackMisc
         QString p = port.toLower().trimmed();
         if (!p.isEmpty())
         {
+            // cppcheck-suppress ignoredReturnValue
             p.toShort(&ok);
             if (!ok)
             {

src/blackmisc/iterator.h

@@ -55,7 +55,8 @@ namespace BlackMisc
             {
                 // Work around lambda's deleted copy assignment operator
                 this->~OutputIterator();
-                return *new (this) OutputIterator(other);
+                new (this) OutputIterator(other);
+                return *this;
             }
 
             //! Destructor.

src/blackmisc/json.h

@@ -431,6 +431,7 @@ namespace BlackMisc
                     if (value.isUndefined())
                     {
                         constexpr bool required = false; //! \fixme add RequiredForJson flag in metaclass system
+                        // cppcheck-suppress knownConditionTrueFalse
                         if (required) { throw CJsonException(QStringLiteral("Missing required member '%1'").arg(member.latin1Name())); }
                     }
                     else

src/blackmisc/simplecommandparser.cpp

@@ -87,6 +87,7 @@ namespace BlackMisc
         const QString p = this->part(index);
         if (p.isEmpty()) { return false; }
         bool ok = false;
+        // cppcheck-suppress ignoredReturnValue
         p.toInt(&ok);
         return ok;
     }