drm/i915: intel_frontbuffer_flip_prepare() doesn't need struct_mutex

So release the lock earlier.

Reviewed-by: Chris wilson <chris@chris-wilson.co.uk>
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
1 file changed