pm2301-charger: Resolve I2C detection problem on ab9540

Signed-off-by: Mustapha Ben Zoubeir <mustapha.ben.zoubeir-nonst@stericsson.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Reviewed-by: Marcus COOPER <marcus.xm.cooper@stericsson.com>
Reviewed-by: Philippe LANGLAIS <philippe.langlais@stericsson.com>
Tested-by: Olivier CLERGEAUD <olivier.clergeaud@stericsson.com>