host cannot recover when connection exceed controller capability

Host can not initiate new connection when exceed controller capability
and connection then drop back to lower than the max. Controller will not
generate connection complete event when initaite LE ll connection request
failed, and host is dead loop waiting for the connection complete
then can not recover. Included a connection complete callback with failure
status when controller capability is exceeded.

bug 17326529
Change-Id: I9b863578dc868456e092f1d060e50d2c9fdcb441