ath6kl: cleanup allocation and getting of the hif dev

Removes verbose debug messages and checks that are just
not needed, and renames the functions to something more
sensible. While we clean this up, just move the routines
above and remove the forward declarations.

Cc: Naveen Singh <nsingh@atheros.com>
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>