video: fbdev: arcfb: add missed free_irq and fix the order of request_irq

The driver forgets to free irq in remove which is requested in
probe.
Add the missed call to fix it.
Also, the position of request_irq() in probe should be put before
register_framebuffer().
Signed-off-by: Chuhong Yuan <hslester96@gmail.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200324132353.21785-1-hslester96@gmail.com

drivers/video/fbdev/arcfb.c

@@ -544,10 +544,6 @@ static int arcfb_probe(struct platform_device *dev)
 	par->cslut[1] = 0x06;
 	info->flags = FBINFO_FLAG_DEFAULT;
 	spin_lock_init(&par->lock);
-	retval = register_framebuffer(info);
-	if (retval < 0)
-		goto err1;
-	platform_set_drvdata(dev, info);
 	if (irq) {
 		par->irq = irq;
 		if (request_irq(par->irq, &arcfb_interrupt, IRQF_SHARED,
@@ -558,6 +554,10 @@ static int arcfb_probe(struct platform_device *dev)
 			goto err1;
 		}
 	}
+	retval = register_framebuffer(info);
+	if (retval < 0)
+		goto err1;
+	platform_set_drvdata(dev, info);
 	fb_info(info, "Arc frame buffer device, using %dK of video memory\n",
 		videomemorysize >> 10);
 
@@ -593,6 +593,8 @@ static int arcfb_remove(struct platform_device *dev)
 
 	if (info) {
 		unregister_framebuffer(info);
+		if (irq)
+			free_irq(((struct arcfb_par *)(info->par))->irq, info);
 		vfree((void __force *)info->screen_base);
 		framebuffer_release(info);
 	}