libertas: use kernel-doc notation, fix comment style

Convert all libertas/ files to use kernel-doc notation instead
of whatever it was (doxygen?).

Add or fix function parameters in several places.

Use expected style for multi-line comments in lots of places.

Remove erroneous /** in multiple places.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Acked-by: Dan Williams <dcbw@redhat.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>