ARM: multi_v7_defconfig: Enable Exynos USB PHY drivers support

Enable the needed kconfig options to have support for Samsung USB 2.0
and USB 3.0 PHY drivers to support the USB PHYs found on Exynos SoCs.

Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
[kgene@kernel.org: savedefconfig]
Signed-off-by: Kukjin Kim <kgene@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>