drivers: gpio: adp5585: fix wrong reg during pin configure

The ADP5585_GPO_OUT_MODE_A is used when configuring initial output
during pin configuration, causing pins configured HIGH is incorrectly
configured as open-drain. Replacing the reg with ADP5585_GPO_DATA_OUT
fixes the issue.

Signed-off-by: Chekhov Ma <chekhov.ma@nxp.com>