power: supply: gpio-charger: Clean up spacing for better readability

Fixed some minor style issues reported by checkpatch.pl. Mainly adjusted the
spacing around operators and type casts to match the kernel coding
conventions. For example:

- Changed `gpios[ndescs-i-1]` to `gpios[ndescs - i - 1]`
- Added space in `(u32*)` to make it `(u32 *)`
- Cleaned up spacing in a `for` loop

No functional changes — just making the code easier to read and consistent
with the rest of the kernel.

Signed-off-by: Darshan R. <rathod.darshan.0896@gmail.com>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>