drm/i915/debug: Select PREEMPT_COUNT when enabling debugging

Required to enable correct wait_for_atomic checks.
Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>

drivers/gpu/drm/i915/Kconfig.debug

@@ -18,6 +18,7 @@ config DRM_I915_WERROR
 config DRM_I915_DEBUG
         bool "Enable additional driver debugging"
         depends on DRM_I915
+        select PREEMPT_COUNT
         default n
         help
           Choose this option to turn on extra driver debugging that may affect