ARM: multi_v7_defconfig: Remove old Samsung USB PHY configs

The old drivers/usb/phy/phy-samsung-usb{2,3} are now deleted since
were replaced by newer drivers that use the Generic PHY framework
but their Kconfig options were left over in multi_v7_defconfig.

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Kukjin Kim <kgene@kernel.org>