rtc: rv3029: get rid of rv3029_get_sr

There is no point in having 2 indirections before calling regmap_read,
especially since rv3029_get_sr also changes the return value without any
good reason. Call regmap_read directly.

Link: https://lore.kernel.org/r/20191214221022.622482-7-alexandre.belloni@bootlin.com


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