libertas: debug output tweaks for lbs_thread

* make debug output match the variable name
* always report that lbs_remove_rtap() has has been exited

Signed-off-by: Holger Schurig <hs4233@mail.mn-solutions.de>
Acked-by: Dan Williams <dcbw@redhat.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>