The WiFi side of the AP6330 WiFi/BT combo module is connected to
mmc1. There are also GPIOs for enable and interrupts. An external
clock from the AC100 RTC is also used.

Enable WiFi on this board by enabling mmc1 and adding the power
sequencing clocks and GPIO, as well as the chip's interrupt line.

For the WiFi module to correctly detect the frequency of its main
oscillator, the external low power clock must be set to 32768 Hz.

Their does not seem to be proper out-of-band interrupt support
for the BCM4330 chip within the AP6330 module. This part is left
out for now.
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>