LU-18231 obd: Add a bitmap for the flags

LU-18231 obd: Add a bitmap for the flags

We will use this bitmap and convert the current bitfields
into bits that are set/cleared/tested using atomic bit operations.

Signed-off-by: Ronnie Sahlberg <rsahlberg@whamcloud.com>
Change-Id: I59ee4621926d0bd79ed0187f6058b888e40315f4
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/56412
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>
Reviewed-by: Timothy Day <timday@amazon.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>