drm/i915: Bump command parser version number.

This was forgotten in

commit d351f6d94893f3ba98b1b20c5ef44c35fc1da124
Author: Francisco Jerez <currojerez@riseup.net>
Date:   Fri May 29 16:44:15 2015 +0300

    drm/i915: Add SCRATCH1 and ROW_CHICKEN3 to the register whitelist.

Signed-off-by: Francisco Jerez <currojerez@riseup.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/i915_cmd_parser.c b/drivers/gpu/drm/i915/i915_cmd_parser.c
index 3977bf3..ad7d7ab 100644
--- a/drivers/gpu/drm/i915/i915_cmd_parser.c
+++ b/drivers/gpu/drm/i915/i915_cmd_parser.c
@@ -1213,6 +1213,7 @@
 	 * 2. Allow access to the MI_PREDICATE_SRC0 and
 	 *    MI_PREDICATE_SRC1 registers.
 	 * 3. Allow access to the GPGPU_THREADS_DISPATCHED register.
+	 * 4. L3 atomic chicken bits of HSW_SCRATCH1 and HSW_ROW_CHICKEN3.
 	 */
-	return 3;
+	return 4;
 }