superio/ite/common: add option for enabling 5 FANs

superio/ite/common: add option for enabling 5 FANs

Some ITEs have more than 3 independent FAN controller outputs. As the
initial implementation assumed only 3 outputs some registers are not
consequently numbered. This change adds macros for accessing those
registers.

Additionally some chips have SmartGuardian always enabled, without the
option for turning it off. For these chips bits that were responsible
for ON/OFF control are either reserved or have different meaning.
Another Kconfig option is added to disable ON/OFF functionality on
platforms that do not support it.

Change-Id: Icd60a16b6b5583a3b981bdc220aac472c2a8f40f
Signed-off-by: Krystian Hebel <krystian.hebel@3mdeb.com>
Reviewed-on: https://review.coreboot.org/c/31616
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Felix Held <felix-coreboot@felixheld.de>
Reviewed-by: Nico Huber <nico.h@gmx.de>