ectool: add new host command to get number of fans
ectool: add new host command to get number of fans

BUG=chrome-os-partner:23803
TEST="ectool pwmgetnumfans" returns correct number of fans on Auron
BRANCH=none

Signed-off-by: Mohammed Habibulla <moch@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/220960
Reviewed-by: Randall Spangler <rspangler@chromium.org>
(cherry picked from commit 75d7e31b9cadb83f7f1cbc54deb9f11de369f006)
Signed-off-by: Duncan Laurie <70662b43bc1a20b57ded72a2b08be88dd0da4841@chromium.org>

Change-Id: I2a1930a8f0965b08558bfb3c6424c571a6149bbb
Reviewed-on: https://chromium-review.googlesource.com/221535
Tested-by: Duncan Laurie <70662b43bc1a20b57ded72a2b08be88dd0da4841@chromium.org>
Reviewed-by: Duncan Laurie <70662b43bc1a20b57ded72a2b08be88dd0da4841@chromium.org>
Commit-Queue: Duncan Laurie <70662b43bc1a20b57ded72a2b08be88dd0da4841@chromium.org>

thehobn/ec,thehobn/ec,thehobn/ec,thehobn/ec