res_hep: Add additional config initialization and validation

res_hep: Add additional config initialization and validation

* Initialize hepv3_runtime_data.sockfd to -1 so that our ao2 destructor
  does not close fd 0

* Add logging output when the required option - capture_address - is not
  specified.

* Remove a no longer relevant #define and correct related documentation

* Pass appropriate flags to aco_option_register so that capture_address
  cannot be the empty string.

ASTERISK-26953 #close

Change-Id: Ief08441bc6596d6f1718fa810e54a5048124f076