mtd: slram: invalid checking of absolute end address

commit c36a7ff4578ab6294885aef5ef241aeec4cdb1f0 upstream.

Fixed parsing end absolute address.

Signed-off-by: Jiri Engelthaler <engycz@gmail.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>