LU-14008 o2iblnd: cleanup

LU-14008 o2iblnd: cleanup

simplify kiblnd_send by avoid code duplication.
lets pickup idle tx first.

Test-Parameters: trivial
HPE-bug-id: LUS-1796
Change-Id: Iaf71a9a3aeb3047a086d4cc0a3cf4f1dbe8944b4
Signed-off-by: Alexey Lyashkov <alexey.lyashkov@hpe.com>
Reviewed-on: https://review.whamcloud.com/40260
Reviewed-by: Chris Horn <chris.horn@hpe.com>
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Alexander Boyko <alexander.boyko@hpe.com>
Reviewed-by: Cyril Bordage <cbordage@whamcloud.com>
Reviewed-by: James Simmons <jsimmons@infradead.org>
Reviewed-by: Oleg Drokin <green@whamcloud.com>