clk: rs9: Drop unused pin_xin field

The pin_xin field in struct rs9_driver_data is unused, drop it.

Signed-off-by: Marek Vasut <marex@denx.de>
Link: https://lore.kernel.org/r/20221216210922.592926-1-marex@denx.de


Reviewed-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>