[media] drivers: staging: davinci_vpfe: use resource_size()

This uses the resource_size() function instead of explicit computation.
Signed-off-by: Silviu-Mihai Popescu <silviupopescu1990@gmail.com>
Acked-by: Lad, Prabhakar <prabhakar.csengg@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/staging/media/davinci_vpfe/dm365_ipipe.c

@@ -1859,5 +1859,5 @@ void vpfe_ipipe_cleanup(struct vpfe_ipipe_device *ipipe,
 	iounmap(ipipe->isp5_base_addr);
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 4);
 	if (res)
-		release_mem_region(res->start, res->end - res->start + 1);
+		release_mem_region(res->start, resource_size(res));
 }

drivers/staging/media/davinci_vpfe/dm365_isif.c

@@ -1953,7 +1953,7 @@ static void isif_remove(struct vpfe_isif_device *isif,
 		res = platform_get_resource(pdev, IORESOURCE_MEM, i);
 		if (res)
 			release_mem_region(res->start,
-					   res->end - res->start + 1);
+					   resource_size(res));
 		i++;
 	}
 }
@@ -2003,7 +2003,7 @@ int vpfe_isif_init(struct vpfe_isif_device *isif, struct platform_device *pdev)
 			status = -ENOENT;
 			goto fail_nobase_res;
 		}
-		res_len = res->end - res->start + 1;
+		res_len = resource_size(res);
 		res = request_mem_region(res->start, res_len, res->name);
 		if (!res) {
 			status = -EBUSY;

drivers/staging/media/davinci_vpfe/dm365_resizer.c

@@ -1995,5 +1995,5 @@ vpfe_resizer_cleanup(struct vpfe_resizer_device *vpfe_rsz,
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 5);
 	if (res)
 		release_mem_region(res->start,
-					res->end - res->start + 1);
+					resource_size(res));
 }