pinctrl: use groupN instead of pinsN for groups

The pinsN group name can be a confusing in some circumstances, so change
it to groupN. Some platforms (e.g. nrf or gd32) are already using
groupN. Documentation and API tests have been updated.

Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>
5 files changed