Qt: Update scrollbars when change byte view format

Update scrollbars when changing display format between hex and
bits view because the height of the phane will change.

Change-Id: I81556c8dbdfb0a34f6c97e76834646a40aed62bb
Reviewed-on: https://code.wireshark.org/review/16336
Reviewed-by: Stig Bjørlykke <stig@bjorlykke.org>

ui/qt/byte_view_text.cpp

@@ -594,6 +594,7 @@ void ByteViewText::setHexDisplayFormat(QAction *action)
 
     recent.gui_bytes_view = action->data().value<bytes_view_type>();
     row_width_ = recent.gui_bytes_view == BYTES_HEX ? 16 : 8;
+    updateScrollbars();
     viewport()->update();
 }