drm: omapdrm: Handle FIFO underflow IRQs internally

As the FIFO underflow IRQ handler just prints an error message to the
kernel log, simplify the code by not registering one IRQ handler per
plane but print the messages directly from the main IRQ handler.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drivers/gpu/drm/omapdrm/omap_drv.h

@@ -102,7 +102,7 @@ struct omap_drm_private {
 
 	/* irq handling: */
 	struct list_head irq_list;    /* list of omap_drm_irq */
-	uint32_t vblank_mask;         /* irq bits set for userspace vblank */
+	uint32_t irq_mask;		/* enabled irqs in addition to irq_list */
 	struct omap_drm_irq error_handler;
 
 	/* atomic commit */