video: udlfb: Use NULL instead of 0

new_back is a pointer. Use NULL instead of 0.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Cc: Bernie Thompson <bernie@plugable.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

drivers/video/udlfb.c

@@ -1166,7 +1166,7 @@ static int dlfb_realloc_framebuffer(struct dlfb_data *dev, struct fb_info *info)
 	int new_len;
 	unsigned char *old_fb = info->screen_base;
 	unsigned char *new_fb;
-	unsigned char *new_back = 0;
+	unsigned char *new_back = NULL;
 
 	pr_warn("Reallocating framebuffer. Addresses will change!\n");