clocksource/drivers/ingenic-sysost: Convert from round_rate() to determine_rate()

The round_rate() clk ops is deprecated, so migrate this driver from
round_rate() to determine_rate() using the Coccinelle semantic patch
appended to the "under-the-cut" portion of the patch.

While changes are being made to 'struct clk_ops', let's also go ahead
and fix the formatting of set_rate so that everything lines up as
expected.

Signed-off-by: Brian Masney <bmasney@redhat.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20250810-clocksource-round-rate-v1-1-486ef53e45eb@redhat.com