drm/i915: Remove stored gtt_alignment

There is no need to store the gtt_alignment as it is either explicitly
set according to the hardware requirements (e.g. scanout) or the
minimum alignment is computed on demand.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index a9c6715..0721469 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -510,10 +510,7 @@
 	 * This is the same as gtt_space->start
 	 */
 	uint32_t gtt_offset;
-	/**
-	 * Required alignment for the object
-	 */
-	uint32_t gtt_alignment;
+
 	/**
 	 * Fake offset for use by mmap(2)
 	 */