translations: Use proper Qt5 extraction command

Refs #69290

Messages.sh

 #! /bin/sh
 
-$XGETTEXT_QT `find . -name '*.cpp'` -o $podir/libringclient_qt.pot
+$EXTRACT_TR_STRINGS `find . -path ./build -prune -o -name '*.cpp'` -o $podir/libringclient_qt.pot

config.ini

@@ -13,4 +13,4 @@ version      = 0.1.0
 docs         = yes
 translations = yes
 gitModule    = yes
-custompo     = sflphone-client-kde_qt
+custompo     = libringclient_qt

genpot.sh

@@ -12,4 +12,3 @@ fi
 cd ..
 mkdir -p po
 IGNORE="/build/" ./build/scripts/extract-messages.sh
-

src/tlsmethodmodel.cpp

@@ -61,7 +61,7 @@ public Q_SLOTS:
    void slotSelectionChanged(const QModelIndex& idx);
 };
 
-const QString TlsMethodModelPrivate::Name::DEFAULT = tr("Default", "Default TLS protocol version");
+const QString TlsMethodModelPrivate::Name::DEFAULT = QObject::tr("Default", "Default TLS protocol version");
 
 TlsMethodModelPrivate::TlsMethodModelPrivate(Account* a) : m_pSelectionModel(nullptr), m_pAccount(a), isRing(false)
 {