TIM: fix 16BPP on big-endian

Despite the QImage::scanLine doc only warning about byte order issues
for 32-bpp formats[0] the same warning seems to apply to 16BPP formats
like QImage::Format_RGB555 as well.

[0]: https://doc.qt.io/qt-6/qimage.html#scanLine

src/imageformats/tim.cpp

@@ -311,6 +311,9 @@ bool TIMHandler::read(QImage *image)
             qCWarning(LOG_TIMPLUGIN) << "TIMHandler::read() error while reading image scanline";
             return false;
         }
+        if (img.format() == QImage::Format_RGB555) {
+            qFromLittleEndian<quint16>(line, size / 2, line);
+        }
         if (conv_4bpp) {
             for (auto x = 0, w = qint32(tmpBuff.size()); x < w; ++x) {
                 auto &&v = tmpBuff.at(x);