meta-facebook: yosemite4: Modify fan rotor fail detection condition

Summary:
Refine fan rotor fail detection logic: determine rotor failure based on
RPM = 0 instead of LCR, and enable oneshot mode to avoid repeated
handling.

Description:
The fan rotor failure detection logic is changed to consider a fan as
failed when its RPM reading is 0, instead of relying on the Lower
Critical (LCR) threshold.

Additionally, oneshot mode is introduced in the failure mechanism to
ensure the failure handler is triggered only once per failure event. The
handler will not re-trigger repeatedly while RPM remains at 0. It will
only rearm when the RPM returns to a non-zero value and fails again
later.

Motivation:
During certain scenarios, fan sensors may temporarily and unexpectedly
trigger the LCR threshold, leading to unintended system DC off events.
To prevent such cases, the failure condition is made stricter by
requiring an actual RPM of 0 before treating the fan as failed. This
helps improve system stability and avoids false positives during
transient conditions.

Test Plan:
- Build and flash the firmware.
- Verify that when more than 2 fan rotors enter the LCR state (but RPM
  is not 0), the system does not DC off the 8 blades.
- Verify that when more than 2 fan rotors report RPM = 0, the system
  logs an event and automatically DC offs the 8 blades.
- Confirm that normal fan behavior is not affected under other
  conditions.

Change-Id: I7764c11b383d128cbeba14de998655f629743a6f
Signed-off-by: Patrick NC Lin <patrick.nc.lin.wiwynn@gmail.com>

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