ath6kl: support for P2P mgmt operations on station interface

This patch enables support for doing P2P management operations like device
discovery on top of a station interface. After group formation, the station
interface will become a P2P GO/client interface as the case may be.

This feature requires modifications to a couple of existing WMI structures and
therefore new command ids and structures have been defined in order to be
compatible with older firmware versions and other chips. The exception here is
the wmi_connect_cmd. Adding a new field to the end of the structure will not
cause any issues with previous firmware versions since firmware only checks for
minimum length of the command. The other structures are of variable length,
hence it was not possible to add new fields to the end.

The new command ids have to be added to the end of enum wmi_cmd_id, so it has
updated to match the firmware.

The driver will support both the 'old' and the 'new' commands for a while by
checking the firmware capabilities.

Signed-off-by: Aarthi Thiruvengadam <athiruve@qca.qualcomm.com>
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>