I2C: OMAP2+: Pass flags up to omap i2c platform_data as well

This is how the driver can find the flags for its implementation
functionality in its platform_data

Cc: patches@linaro.org
Cc: Ben Dooks <ben-linux@fluff.org>
Reported-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Andy Green <andy.green@linaro.org>
Signed-off-by: Tony Lindgren <tony@atomide.com>