WPS: Add option for using random UUID

WPS: Add option for using random UUID

If the uuid configuration parameter is not set, wpa_supplicant generates
an UUID automatically to allow WPS operations to proceed. This was
previously always using an UUID generated from the MAC address. This
commit adds an option to use a random UUID instead. The type of the
automatically generated UUID is set with the auto_uuid parameter: 0 =
based on MAC address (default; old behavior), 1 = random UUID.

Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>