rme: convince PyQt to keep the RME mixer panel as small as possible. However, PyQt...

rme: convince PyQt to keep the RME mixer panel as small as possible.  However, PyQt continues to insist on making the mixer window as a whole much larger vertically than is desired, resulting in a large blank area below the RME mixer panel.  If the RME mixer panel is set to a fixed size this extra vertical space is still added to the window, resulting in the generic mixer controls taking up the space.  This suggests that there's something about the higher level window that's causing this.  But what?

git-svn-id: svn+ssh://ffado.org/ffado/trunk@2291 2be59082-3212-0410-8809-b0798e1608f0