- Enable interrupts only at the end of epic_attach() when all the   other initializations succeeded. - Initialize the TX and RX rings in epic_attach() rather than in   epic_init() where we're not supposed to fail.  Similarly, free   the TX and RX rings in epic_detach() rather than in epic_stop(). - Change epic_init() to be a void function now that it can't fail.   Also change its parameter to a void * so that we have a correct   prototype for if_init. - Now that epic_init() has a correct prototype, don't cast the   function pointer when initializing if_init. - Fix nearby style bugs.
- Enable interrupts only at the end of epic_attach() when all the
  other initializations succeeded.
- Initialize the TX and RX rings in epic_attach() rather than in
  epic_init() where we're not supposed to fail.  Similarly, free
  the TX and RX rings in epic_detach() rather than in epic_stop().
- Change epic_init() to be a void function now that it can't fail.
  Also change its parameter to a void * so that we have a correct
  prototype for if_init.
- Now that epic_init() has a correct prototype, don't cast the
  function pointer when initializing if_init.
- Fix nearby style bugs.

jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase