Function devm_kzalloc() will return a NULL pointer. However, in function
isp1704_charger_probe(), the return value of devm_kzalloc() is directly
used without validation. This may result in a bad memory access bug.

Fixes: 34a10961 ("isp1704_charger: Add DT support")
Signed-off-by: Pan Bian <bianpan2016@163.com>
Reviewed-by: Pali Rohár <pali.rohar@gmail.com>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>