staging/lustre/osc: remove obsolete llog handling code

In osc_request.c there is no reason to handle any llog contexts since
they are never setup. Remove the functions unused function
osc_llog_init() and the obsolete function osc_llog_finish(). Remove
the llog cleanup code in osc_disconnect() and osc_precleanup().

Signed-off-by: John L. Hammond <john.hammond@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>