drm/msm/dsi: Delete an unnecessary check before the function call "dsi_destroy"

The dsi_destroy() function tests whether its argument is NULL and then
returns immediately. Thus the test around the call is not needed.

This issue was detected by using the Coccinelle software.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Rob Clark <robdclark@gmail.com>

drivers/gpu/drm/msm/dsi/dsi.c

@@ -110,9 +110,7 @@ static struct msm_dsi *dsi_init(struct platform_device *pdev)
 	return msm_dsi;
 
 fail:
-	if (msm_dsi)
-		dsi_destroy(msm_dsi);
-
+	dsi_destroy(msm_dsi);
 	return ERR_PTR(ret);
 }