ARM: exynos: defconfig update

This turns on a number of configs that are useful on the Chromebook, but also
good to have on in general:

* USB host and MMC drivers(!)
* I2C GPIO arbitration driver
* CYAPA trackpad driver
* simplefb
* CROS EC and keyboard drivers
* S5M8767 driver
* MAX77686 drivers
* MAX8997 driver
* DEVTMPFS + mount
* DM_CRYPT (as module)
* CRYPTOLOOP
* HIGHMEM
* PRINTK timestamps

This also turns off DEBUG_LL, and switches the hardcoded Samsung lowlevel
uart to uart 3 (which is only used to show the "uncompressing kernel"
message at boot, it seems).

Signed-off-by: Olof Johansson <olof@lixom.net>
Reviewed-by: Doug Anderson <dianders@chromium.org>
Tested-by: Tushar Behera <tushar.behera@linaro.org>
Acked-by: Kukjin Kim <kgene.kim@samsung.com>