power: supply: qti_battery_charger: add support for wireless FW CRC check

Currently, wireless FW update is done by the user once a FW file
is pushed to one of the firmware folders and with user writing
to "wireless_fw_update" or "wireless_fw_force_update" under
/sys/class/qcom-battery.

As per the recent requirements to add CRC check during wireless
firmware update process, add "wireless_fw_crc" property through
which the user can pass CRC before doing FW update. Since this
adds extra time for validating the CRC, increase the wait time
for FW update completion from 500 ms to 1 second. Also, print an
error log if FW update is not done.

E.g.

echo 0x1234 > /sys/class/qcom-battery/wireless_fw_crc
echo 1 > /sys/class/qcom-battery/wireless_fw_update

Now with adding this support, if CRC is not set, FW update would
fail as the charger firmware validates the CRC passed.

Change-Id: Id66cd84984b6206bf866ee1f18f7b32d9090c5dd
Signed-off-by: Subbaraman Narayanamurthy <subbaram@codeaurora.org>