[patch] New htc-bbkeys (bit-banging keyboard) driver

Hi,

Attached is a patch that generalizes support for the front keypad chip
that is present on HTC Apache. I'm doing this because the same chip
is also on HTC Hermes. (There is suspicion that some blueangel phones
also have it.)

For those curious, the chip is suspected to be some kind of
micro-controller. It uses a pair of gpio pins (with a psuedo-i2c
protocol) to communicate with the processor. It controls the front
keypad, the front LEDs, and the LCD power settings.

Note that there is one ugliness in this driver. I needed to be able
to control the chip early during the boot so that I can enable the LCD
power. However, at that stage, the input subsystem is not yet
initialized. So, I've added a hack to the driver to delay keyboard
initialization until later in the boot.

Comments welcome.

-Kevin