board-redridge: changed fuel gauge gpio pin name to max_fg_alert

board-redridge: changed fuel gauge gpio pin name to max_fg_alert

BZ: 31370

This patch modifies the gpio pin name to max_fg_alert. This will
avoid the dependency to know device id as the alert pin is present
on all platforms we can have single unique gpio pin name.

Change-Id: I7eb79a44d3ea2f5743da741dd7ca668f0a89093c
Signed-off-by: Ramakrishna Pallala <ramakrishna.pallala@intel.com>
Reviewed-on: http://android.intel.com:8080/43091
Reviewed-by: Kanigeri, Hari K <hari.k.kanigeri@intel.com>
Reviewed-by: Tc, Jenny <jenny.tc@intel.com>
Reviewed-by: Hari, NeelamX <neelamx.hari@intel.com>
Reviewed-by: Lebouc, Christophe <christophe.lebouc@intel.com>
Tested-by: Lebouc, Christophe <christophe.lebouc@intel.com>
Reviewed-by: buildbot <buildbot@intel.com>
Tested-by: buildbot <buildbot@intel.com>