rtc: pcap: Drop no-op remove function

A remove callback that just returns 0 is equivalent to no callback at
all as can be seen in platform_remove(). So simplify accordingly.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20231002080529.2535610-8-u.kleine-koenig@pengutronix.de


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