leds: mt6323: move period calculation

leds: mt6323: move period calculation

clang static analysis reports this problem

leds-mt6323.c:275:12: warning: Division by zero
        duty_hw = MT6323_CAL_HW_DUTY(*delay_on, period);
                  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

This is because period can be 0.

	period = *delay_on + *delay_off;

There is a later check that *delay_on/off are valid.

	if (!*delay_on && !*delay_off) {
		*delay_on = 500;
		*delay_off = 500;
	}

Setting the delay_on/off means period needs to be recalculated
anyway.  So move the period statements after this check.

Fixes: 216ec6cc4c19 ("leds: Add LED support for MT6323 PMIC")
Signed-off-by: Tom Rix <trix@redhat.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>