power: supply: sbs-battery: Cleanup removal of chip->pdata

There where still a few lingering references to pdata after commit
power: supply: sbs-battery: simplify DT parsing.

Remove pdata from struct·sbs_info and conditional checks to ser if this
was set from the i2c read / write functions.
Instead of call max in each function for incrementing poll_retry_count
do it once in the probe function.
Fixup null pointer dereference in to pdata in sbs_external_power_changed.
Change retry counts to u32 to avoid need for max.

Signed-off-by: Phil Reid <preid@electromag.com.au>
Signed-off-by: Sebastian Reichel <sre@kernel.org>