clk: pwm: Don't reconfigure running PWM at probe time

clk: pwm: Don't reconfigure running PWM at probe time

If the PWM is enabled already when .probe() is entered, period and
duty_cycle are updated which essentially corresponds to a clock frequency
change. This is unusual and surprising. So update the settings only when
the clock gets prepared.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
Link: https://lore.kernel.org/r/a974f1147e1a080bf5ad7f1752c92b24516df284.1746006578.git.ukleinek@baylibre.com
Signed-off-by: Stephen Boyd <sboyd@kernel.org>