ARM: imx_v6_v7_defconfig: Enable CRYPTO_DEV_MXS_DCP

This block is present in 6sl, 6sll and 6ull so it should be enabled in
the default imx kernel config.

Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>
Reviewed-by: Fabio Estevam <festevam@gmail.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>