cm-fx6: GPIO7_13: preprogram as physical HOME key

As soft keys do not appear on the Startek display (seemingly, due to
a bug in Android), preprogram GPIO 205 (GPIO7_13) as hardware HOME
key.
On newer releases of SB-FX6, this GPIO is wired to SW6 button.

This patch is backported from andromeda:JellyBean-4.3.

Signed-off-by: Andrey Gelman <andrey.gelman@compulab.co.il>
cm-fx6: i2c-mux: enable I2C multiplexing

Newer releases of SB-FX6 use I2C bus multiplexing.
This patch has zero effect on non-multiplexed I2C bus, while
eliminates undefined state on multiplexed bus.

Notice:
As ICS release is being minimally maintained, we do not add DVI
EDID-reading capability.

This patch is backported from compulab/utilite branch.

Signed-off-by: Andrey Gelman <andrey.gelman@compulab.co.il>
pca953x: add power management support

Add suspend/resume functionality to PCA953x driver.
Limitation:
Seemingly does not satisfy PCA957x (also covered by pca953x.c)
requirements.

This patch was originally authored by Saeed Bishara of Marvell.
Reference:
https://lists.ubuntu.com/archives/kernel-team/2009-August/007035.html

Signed-off-by: Andrey Gelman <andrey.gelman@compulab.co.il>
sb-fx6: pca953x: enable DVI transmitter

Enable DVI transmitter by default.
In the past, DVI transmitter has been enabled accidentally, due to
pca953x eGPIO default state (input with a pull-up resistor).

Additionally, set e few more eGPIO(s).

Signed-off-by: Andrey Gelman <andrey.gelman@compulab.co.il>