drm/i915: initialize gt_lock early with other spin locks

commit 14c5cec5d0cd73e7e9d4fbea2bbfeea8f3ade871 upstream.

commit 181d1b9e31c668259d3798c521672afb8edd355c
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date:   Sun Jul 21 13:16:24 2013 +0200

    drm/i915: fix up gt init sequence fallout

moved dev_priv->gt_lock initialization after use. Do the initialization
much earlier with other spin lock initializations.

Reported-by: Sedat Dilek <sedat.dilek@gmail.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Zhouping Liu <zliu@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>