drm/i915/irq: Fix kernel-doc warnings

Add the dev parameter for the functions i915_enable_asle_pipestat() and
i915_reset_and_wakeup() to the kernel-doc to fix the following warnings:

.//drivers/gpu/drm/i915/i915_irq.c:586: warning: No description found for parameter 'dev'
.//drivers/gpu/drm/i915/i915_irq.c:2400: warning: No description found for parameter 'dev'
Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/i915_irq.c

@@ -581,6 +581,7 @@ i915_disable_pipestat(struct drm_i915_private *dev_priv, enum pipe pipe,
 
 /**
  * i915_enable_asle_pipestat - enable ASLE pipestat for OpRegion
+ * @dev: drm device
  */
 static void i915_enable_asle_pipestat(struct drm_device *dev)
 {
@@ -2392,6 +2393,7 @@ static void i915_error_wake_up(struct drm_i915_private *dev_priv,
 
 /**
  * i915_reset_and_wakeup - do process context error handling work
+ * @dev: drm device
  *
  * Fire an error uevent so userspace can see that a hang or error
  * was detected.