Addition of device tree support for DA9210.
Two files are modified, the driver source file and the binding document.

Updates for the regulator source file include an .of_match_table entry and
node match checking in the probe() function for a compatible da9210 string.

Minor binding documentation changes have been made to the title and the
example.
Tested-by: Steve Twiss <stwiss.opensource@diasemi.com>
Signed-off-by: Steve Twiss <stwiss.opensource@diasemi.com>
Signed-off-by: Mark Brown <broonie@kernel.org>