ARM: exynos_defconfig: Enable s5p-secss driver

The Exynos SoC provides a Security SubSystem block for accelerating some
cryptographic operations. Enable the driver for it - s5p-secss to
utilize the hardware acceleration.

Currently the s5p-secss driver supports AES in CBC and ECB modes.
However on Odroid XU4 (Exynos5422) and Trats2 (Exynos4412) boards this
change introduces one booting error (because of unaligned buffers):

	alg: skcipher: encryption failed on chunk test 1 for ecb-aes-s5p: ret=22

The cbc-aes-s5p properly registers itself and passes self-tests.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Reviewed-by: Anand Moon <linux.amoon@gmail.com>
Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>