EX-6269 osc: Add BRW_COMPRESSED flag to reads

EX-6269 osc: Add BRW_COMPRESSED flag to reads

We need to add the BRW_COMPRESSED flag to reads so servers
can know if the client is able to decompress data.

This lets servers decide if a client can be sent compressed
data and the result won't be nonsense/corruption.  This is
important for future support of GPU direct, where the
server will need to do the decompression.

Signed-off-by: Patrick Farrell <pfarrell@whamcloud.com>
Change-Id: I36b5b73f983ce8f2e5297c3e9dc778a5eca54e6a
Reviewed-on: https://review.whamcloud.com/c/ex/lustre-release/+/51960
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>