create a log category for OCC::Theme class

Signed-off-by: Matthieu Gallien <matthieu.gallien@nextcloud.com>

src/libsync/theme.cpp

@@ -32,6 +32,7 @@
 #include <QPainter>
 #include <QJsonDocument>
 #include <QJsonArray>
+#include <QLoggingCategory>
 
 #ifdef Q_OS_WIN
 #include <windows.h>
@@ -76,6 +77,8 @@ bool isWindows11OrGreater() {
 
 namespace OCC {
 
+Q_LOGGING_CATEGORY(lcTheme, "nextcloud.gui.theme", QtInfoMsg)
+
 Theme *Theme::_instance = nullptr;
 
 Theme *Theme::instance()