ASoC: rt5677: Add OF device ID table

The driver doesn't have a struct of_device_id table but supported devices
are registered via Device Trees. This is working on the assumption that a
I2C device registered via OF will always match a legacy I2C device ID and
that the MODALIAS reported will always be of the form i2c:<device>.

But this could change in the future so the correct approach is to have an
OF device ID table if the devices are registered via OF.

Before this patch:

$ modinfo sound/soc/codecs/snd-soc-rt5677.ko | grep alias
alias:          i2c:RT5677CE:00
alias:          i2c:rt5676
alias:          i2c:rt5677

After this patch:

$ modinfo sound/soc/codecs/snd-soc-rt5677.ko | grep alias
alias:          of:N*T*Crealtek,rt5677C*
alias:          of:N*T*Crealtek,rt5677
alias:          i2c:RT5677CE:00
alias:          i2c:rt5676
alias:          i2c:rt5677

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>