NFC: Define secure element connectivity and transaction events

The SE_CONNECTIVITY event is for an SE to request connection to e.g. a
modem. The SE_TRANSACTION one is sent when an application running on a
specific SE wants to notify the host CPU about the end of a transaction.
Those events respectively map to the EVT_CONNECTIVITY and the
EVT_TRANSACTION HCI events.

Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>