drm: sti: fix check for clk_pix_main

copy-paste wasn't followed by editing, do it.
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

drivers/gpu/drm/sti/sti_hqvdp.c

@@ -1025,7 +1025,7 @@ static int sti_hqvdp_probe(struct platform_device *pdev)
 	/* Get clock resources */
 	hqvdp->clk = devm_clk_get(dev, "hqvdp");
 	hqvdp->clk_pix_main = devm_clk_get(dev, "pix_main");
-	if (IS_ERR(hqvdp->clk) || IS_ERR(hqvdp->clk)) {
+	if (IS_ERR(hqvdp->clk) || IS_ERR(hqvdp->clk_pix_main)) {
 		DRM_ERROR("Cannot get clocks\n");
 		return -ENXIO;
 	}