max17042: Add power supply attribute for Coloumb Counter

max17042: Add power supply attribute for Coloumb Counter

BZ: 33602

This patch adds the support for CHARGER_COUNTER power supply
attribute to max17042/47 driver.

Note:QH(Charge Counter) register is not documented in max17042 the Spec.

Change-Id: I0d0c0e42f6905fcf63a16ddd6e5b003909fac907
Signed-off-by: Ramakrishna Pallala <ramakrishna.pallala@intel.com>
Reviewed-on: http://android.intel.com:8080/46297
Reviewed-by: Tc, Jenny <jenny.tc@intel.com>
Reviewed-by: Koskinen, Ilkka <ilkka.koskinen@intel.com>
Reviewed-by: Jena, TapanX <tapanx.jena@intel.com>
Tested-by: Kallappa Manjanna, MadhukumarX <madhukumarx.kallappa.manjanna@intel.com>
Reviewed-by: buildbot <buildbot@intel.com>
Tested-by: buildbot <buildbot@intel.com>