ptp: idt82p33: use rsmu driver to access i2c/spi bus

rsmu (Renesas Synchronization Management Unit ) driver is located in
drivers/mfd and responsible for creating multiple devices including
idt82p33 phc, which will then use the exposed regmap and mutex
handle to access i2c/spi bus.

Signed-off-by: Min Li <min.li.xe@renesas.com>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Link: https://lore.kernel.org/r/1646748651-16811-1-git-send-email-min.li.xe@renesas.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>