watchdog: s3c2410_wdt.c: Convert release_resource to release_region/release_mem_region

Request_mem_region should be used with release_mem_region, not
release_resource.

The semantic match that finds this problem is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
expression x,E;
@@
*x = request_mem_region(...)
... when != release_mem_region(x)
    when != x = E
* release_resource(x);
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Cc: stable <stable@kernel.org>