pxa2xx: Auto-assign name for i2c bus in i2c_init_bus.

pxa2xx: Auto-assign name for i2c bus in i2c_init_bus.

If a name is provided, the same name is assigned to both the I2C
controllers. Leaving it NULL, causes names to be automatically
assigned with an ID suffix, giving unique names to each
controller. This helps us to uniquely identify each controller in the
device tree, for example when adding an I2C device.

Signed-off-by: Vijay Kumar B. <vijaykumar@zilogic.com>
Reviewed-by: Deepak S. <deepak@zilogic.com>
Message-id: 1476351885-8905-1-git-send-email-vijaykumar@zilogic.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>