libertas: Remove unused exports

The libertas driver exports a number of symbols with no in-tree users;
remove these unused exports.  lbs_reset_device() is completely unused, with
no callers at all, so remove the function completely.

A couple of these unused exported symbols are static, which causes the
following build error on ia64 with gcc 4.2.3:

    drivers/net/wireless/libertas/main.c:1375: error: __ksymtab_lbs_remove_mesh causes a section type conflict
    drivers/net/wireless/libertas/main.c:1354: error: __ksymtab_lbs_add_mesh causes a section type conflict

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