power: smb135x-charger: skip APSD rerun if battery is absent

When APSD reruns, it turns off the switcher preventing the power
drawn from the USB charger. If battery is not present then the device
will run without any input power when APSD rerun happens. This will
cause a brownout.

Prevent running APSD while battery is missing. The USB type detected
may not be correct but this prevents brownout.

CRs-Fixed: 834342
Change-Id: I933246b3bbb2abc97bdc927d5ab2a882fb100e68
Signed-off-by: Abhijeet Dharmapurikar <adharmap@codeaurora.org>