MIPS: use resource_size

Use resource_size rather than a verbose computation on
the end and start fields.

The semantic patch that makes these changes is as follows:
(http://coccinelle.lip6.fr/)

<smpl>
@@ struct resource ptr; @@
- (ptr.end - ptr.start + 1)
+ resource_size(&ptr)
</smpl>
Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Paul Burton <paulburton@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: kernel-janitors@vger.kernel.org
Cc: James Hogan <jhogan@kernel.org>
Cc: linux-mips@vger.kernel.org
Cc: linux-kernel@vger.kernel.org

arch/mips/kernel/setup.c

@@ -515,8 +515,7 @@ static void __init request_crashkernel(struct resource *res)
 	ret = request_resource(res, &crashk_res);
 	if (!ret)
 		pr_info("Reserving %ldMB of memory at %ldMB for crashkernel\n",
-			(unsigned long)((crashk_res.end -
-					 crashk_res.start + 1) >> 20),
+			(unsigned long)(resource_size(&crashk_res) >> 20),
 			(unsigned long)(crashk_res.start  >> 20));
 }
 #else /* !defined(CONFIG_KEXEC)		*/
@@ -698,8 +697,7 @@ static void __init arch_mem_init(char **cmdline_p)
 	mips_parse_crashkernel();
 #ifdef CONFIG_KEXEC
 	if (crashk_res.start != crashk_res.end)
-		memblock_reserve(crashk_res.start,
-				 crashk_res.end - crashk_res.start + 1);
+		memblock_reserve(crashk_res.start, resource_size(&crashk_res));
 #endif
 	device_tree_init();
 	sparse_init();