guybrush: Only enable fan PWM in S0
guybrush: Only enable fan PWM in S0

The EC_FAN_PWM# pull up in S0 power domain. So restrict fan control to
when S0_PGOOD is asserted.

BUG=b:188534598
TEST=Build and run, fan still works
BRANCH=None

Signed-off-by: Rob Barnes <3ced0940a2329ce70499686f01d3d60685ec66ed@google.com>
Change-Id: Ifd4a6405004aef1628c1b272bfce2de7a4b8d8d6
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/2906293
Reviewed-by: Diana Z <cb2016afc7183e5356c690dc63b4ba817470501a@chromium.org>

coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec,coreboot/chrome-ec