power: qpnp-smbcharger: disable charging for unknown batteries

Currently, we disable the charging only when the battery is not
recognized. Also if a battery happens to match the default
OTP profile, then the charging should be disabled. In addition,
charging is disabled by using USB_SUSPEND_SRC_BIT which is
not desirable as it limits the inflow current.

Disable the charging by using the charge_en bit which will still
allow the USB current in and block it going into the battery.

CRs-Fixed: 810866
Change-Id: I55549938f514780701a10e3239b6172c9dbd1108
Signed-off-by: Xiaozhe Shi <xiaozhes@codeaurora.org>