rtc: rx8025: implement RX-8035 support

The RX-8035 is a newer RTC from EPSON that is very
similar to the RX-8025.

The key difference is in the oscillation stop (XSTP)
bit which is inverted on the RX-8035.

Signed-off-by: Mathew McBride <matt@traverse.com.au>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20210709044518.28769-2-matt@traverse.com.au