ARM: multi_v7_defconfig: Enable Cypress APA I2C Trackpad support

The Cypress All Points Addressable (APA) I2C Trackpad is used in the
Samsung Exynos 5250 Snow Chromebook. Build the driver as a module so
the device is supported.

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