ARM: multi_v7_defconfig: Enable Allwinner P2WI, PWM, DMA_SUN6I, cryptodev

Enable drivers for Allwinner P2WI, PWM, cryptodev (Security System) and
sun6i DMA engine. Also enable EXTCON as PHY_SUN4I_USB depends on it.

Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>