LU-9859 libcfs: remove Lustre specific bitmap handling

LU-9859 libcfs: remove Lustre specific bitmap handling

Only the NRS TBF handling uses the Lustre specific bitmap
handling. Convert to the Linux bitmap API and remove the
Lustre specific bitmap handling.

Test-Parameters: trivial testlist=sanityn env=ONLY=77
Change-Id: I58dcf869778d6cf6349c16e73d75e53735ffb97d
Signed-off-by: James Simmons <jsimmons@infradead.org>
Reviewed-on: https://review.whamcloud.com/48222
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Arshad Hussain <arshad.hussain@aeoncomputing.com>
Reviewed-by: Jian Yu <yujian@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>