drm/tilcdc: Correct misspelling in error message

This error message will be printed when a FIFO underflow irq has
triggered. Since this happens sometimes and the error message will be
displayed on the console, it should have a correct spelling.
Signed-off-by: NDaniel Schultz <d.schultz@phytec.de>
Signed-off-by: NJyri Sarha <jsarha@ti.com>

drivers/gpu/drm/tilcdc/tilcdc_crtc.c

@@ -803,7 +803,7 @@ irqreturn_t tilcdc_crtc_irq(struct drm_crtc *crtc)
 	}
 
 	if (stat & LCDC_FIFO_UNDERFLOW)
-		dev_err_ratelimited(dev->dev, "%s(0x%08x): FIFO underfow",
+		dev_err_ratelimited(dev->dev, "%s(0x%08x): FIFO underflow",
 				    __func__, stat);
 
 	/* For revision 2 only */