Merge r269353:

Merge r269353:

Fix breakage introduced by r256843: removing the SA_CCB_WAITING bit
left some of the decisions based on its counterpart, SA_CCB_BUFFER_IO
being random.  As a result, propagation of the residual information
for the SPACE command was broken, so the number of filemarks
encountered during a SPACE operation was miscalculated.  Consequently,
systems relying on properly tracked filemark counters (like Bacula)
fell apart.

The change also removes a switch/case in sadone() which r256843
degraded to a single remaining case label.

PR:		192285

git-svn-id: svn://svn.freebsd.org/base/stable/10@269717 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f