It's magic, but it seems to work.

This fixes a regression introduced in

commit 1bb9e632
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date:   Tue Jul 8 10:02:43 2014 +0200

    drm/i915: Only unbind vgacon, not other console drivers

My best guess is that the vga fbdev driver falls over if we rip out
parts of vgacon. Hooray.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=82439
Cc: stable@vger.kernel.org (v3.16+)
Reported-and-tested-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Acked-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>