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>