davinci: Add LCD Graphics support for DA830/OMAP-L137 EVM

Add graphics support for the Sharp LCD035Q3DG01 graphical
LCD that's on the User Interface (UI) daughter card of the
DA830/OMAP-L137 EVM.

The LCD shares EMIFA lines with the NAND and NOR devices that
are also on the UI card so those lines are shared via a couple
of muxes.  The muxes are controlled by the 'MUX_MODE' line on
the UI card.  The 'MUX_MODE' line is controlled by pin P6 of
a pcf8574 i2c expander that's at i2c address 0x3f on UI card.
The i2c expander is controlled using the gpio infrastructure
from the board code using the 'setup()' and 'teardown()'
routines.

Signed-off-by: Steve Chen <schen@mvista.com>
Signed-off-by: Mark A. Greer <mgreer@mvista.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>