lib: i2c-dev: create a wrapper

An overall wrapper to allow for us to re-route i2c operations
to mpsse or i2cdev as needed.

Signed-off-by: Nishanth Menon <nm@ti.com>
sandbox: provide dummy i2c ops

Now that we can re-route i2c ops, just do a dummy fall through
function

Signed-off-by: Nishanth Menon <nm@ti.com>
powertool: ina226/bus: use void * as function pointer to bus

Drop the remapping and just use void * pointer to indicate I2C bus
information

Signed-off-by: Nishanth Menon <nm@ti.com>
lib: omapconf: increase max title size to 150

This is needed in some cases for longer titles

Signed-off-by: Nishanth Menon <nm@ti.com>
powertool: pm_bus: increase length of i2c string

With MPSSE, we'd have vendorid, product id and iserial
and 3 characters wont suffice here.

Signed-off-by: Nishanth Menon <nm@ti.com>
lib: add libmpsse and a wrapper

From https://github.com/devttys0/libmpsse
which in turn is from
https://code.google.com/p/libmpsse/

Also provide a wrapper and build option for libmpsse based access.

I2C ID indicates which mpssee device to use.
example:
-	i2c = "1"
+	i2c = "0x0403:0x6010:2:FTVFSHEZ"
Here:
vendorid = 0x0403
productid = 0x6010
interface = 2(interface B)
serial = FTVFSHEZ

Signed-off-by: Nishanth Menon <nm@ti.com>
README.md: add information about Total Phase's Aardvark I2c adapter

Thanks to Mike Turquette, this is a cool access path as well.

Signed-off-by: Nishanth Menon <nm@ti.com>