rtc: rv3029: use proper name for the driver

The correct name for the rtc is rv3029. c2 is actually the package form
factor rv3029c3 exists and simply has a smaller form factor.

Link: https://lore.kernel.org/r/20191214221022.622482-2-alexandre.belloni@bootlin.com


Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>