I2C: OMAP1/OMAP2+: create omap I2C functionality flags for each cpu_... test

These represent the 8 kinds of implementation functionality
that up until now were inferred by the 16 remaining cpu_...()
tests in the omap i2c driver.

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>