[ARM] pxa: avoid NULL dereferencing in error handling of ssp.c

[ARM] pxa: avoid NULL dereferencing in error handling of ssp.c

The assignments of res to the results of the two calls to
platform_get_resource make it impossible to use res in the error handling
code in the arguments to release_mem_region.

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

// <smpl>
@r exists@
expression E, E1;
identifier f;
statement S1,S3;
iterator iter;
@@

if ((E == NULL && ...) || ...)
{
 ... when != false ((E == NULL && ...) || ...)
     when != true  ((E != NULL && ...) || ...)
     when != iter(E,...) S1
     when != E = E1
(
 sizeof(E->f)
|
* E->f
)
 ... when any
 return ...;
}
else S3
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Eric Miao <eric.y.miao@gmail.com>