MAINTAINERS: add maintainer for Renesas RIIC driver

The RIIC I2C controller is used in Renesas RZ/A SoCs.

Signed-off-by: Chris Brandt <chris.brandt@renesas.com>
[wsa: added documentation file]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
1 file changed