drm/tilcdc: remove broken error handling

Remove broken error handling. The condition for handling the
LCDC_SYNC_LOST and LCDC_FIFO_UNDERFLOW could never be satisfied as the
LCDC_SYNC_LOST interrupt is not enabled. Also the requirement to have
both LCDC_SYNC_LOST and LCDC_FIFO_UNDERFLOW fired at once before
handling the error looks weird.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
[Added description to the patch]
Signed-off-by: Jyri Sarha <jsarha@ti.com>

drivers/gpu/drm/tilcdc/tilcdc_crtc.c

@@ -658,12 +658,7 @@ irqreturn_t tilcdc_crtc_irq(struct drm_crtc *crtc)
 	struct tilcdc_drm_private *priv = dev->dev_private;
 	uint32_t stat = tilcdc_read_irqstatus(dev);
 
-	if ((stat & LCDC_SYNC_LOST) && (stat & LCDC_FIFO_UNDERFLOW)) {
-		stop(crtc);
-		dev_err(dev->dev, "error: %08x\n", stat);
-		tilcdc_clear_irqstatus(dev, stat);
-		start(crtc);
-	} else if (stat & LCDC_PL_LOAD_DONE) {
+	if (stat & LCDC_PL_LOAD_DONE) {
 		tilcdc_clear_irqstatus(dev, stat);
 	} else {
 		struct drm_pending_vblank_event *event;