drm: drop DRIVER_HAVE_IRQ flag for some drivers

Since commit 4984979b9b ("drm/irq: simplify irq checks in
drm_wait_vblank"), the drm driver feature flag DRIVER_HAVE_IRQ is only
required for drivers that have an IRQ handler managed by the DRM core.
Some drivers, armada, etnaviv, kirin and sti, set this flag without
.irq_handler setup in drm_driver.  These drivers manage IRQ handler
by themselves and the flag DRIVER_HAVE_IRQ makes no sense there.

Drop the flag for these drivers to avoid confusion.

Signed-off-by: Shawn Guo <shawnguo@kernel.org>
Cc: Vincent Abriou <vincent.abriou@st.com>
Cc: Xinliang Liu <z.liuxinliang@hisilicon.com>
Acked-by: Russell King <rmk+kernel@armlinux.org.uk> (for armada and etnaviv)
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1471331168-5601-1-git-send-email-shawnguo@kernel.org

drivers/gpu/drm/armada/armada_drv.c

@@ -211,7 +211,7 @@ static struct drm_driver armada_drm_driver = {
 	.desc			= "Armada SoC DRM",
 	.date			= "20120730",
 	.driver_features	= DRIVER_GEM | DRIVER_MODESET |
-				  DRIVER_HAVE_IRQ | DRIVER_PRIME,
+				  DRIVER_PRIME,
 	.ioctls			= armada_ioctls,
 	.fops			= &armada_drm_fops,
 };