rv3029_read_regs and rv3029_write_regs are simply calling
regmap_bulk_{read,write}. Drop them and call regmap_{,bulk}_{read,write} as
appropriate.

Link: https://lore.kernel.org/r/20191214221022.622482-10-alexandre.belloni@bootlin.comSigned-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>