EM/Charger: sysfs reflecting charger type as USB_DCP for wall charger

EM/Charger: sysfs reflecting charger type as USB_DCP for wall charger

BZ: 25505

Added the code to reflect the charger type as USB_DCP when wall charger
is connected to differentiate between the different type of USB chargers.

Change-Id: Ic3f5bcf993500456b4b93143f795439a848f606a
Signed-off-by: Pandey Raj <raj.pandey@intel.com>
Reviewed-on: http://android.intel.com:8080/37551
Reviewed-by: Tc, Jenny <jenny.tc@intel.com>
Reviewed-by: Natarajan, SaravananX <saravananx.natarajan@intel.com>
Tested-by: Kallappa Manjanna, MadhukumarX <madhukumarx.kallappa.manjanna@intel.com>
Reviewed-by: buildbot <buildbot@intel.com>
Tested-by: buildbot <buildbot@intel.com>