staging/lustre/libcfs: remove unused cfs_timer_done

Remove the cfs_timer_done function in the libcfs
kernel module since it is not used anywhere.

Signed-off-by: James Simmons <uja.ornl@yahoo.com>
Signed-off-by: frank zago <fzago@cray.com>
Reviewed-on: http://review.whamcloud.com/13917
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-6245


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