ARM: dts: s5pv210: Add si470x FM radio to Galaxy S

Add support for the Silicon Labs si4709 FM radio, which can be found
on Galaxy S GT-i9000 (but not on most of other Aries variants).

Signed-off-by: Paweł Chmiel <pawel.mikolaj.chmiel@gmail.com>
Signed-off-by: Jonathan Bakker <xc-racer2@live.ca>
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>