The fragment flush code tries to send the active fragment before
sending any queued fragments. This could cause osc messages to arrive
out-of-order at the target (bad). Ensure ordering by alway sending
the active fragment after sending queued fragments.
This commit also fixes a bug when a synchronization message (unlock,
flush, complete) can not be packed at the end of an existing active
fragment. In this case the source process will end up sending 1 more
fragment than claimed in the synchronization message. To fix the issue
a check has been added that fixes the fragment count if this situation
is detected.
Signed-off-by: Nathan Hjelm <hjelmn@lanl.gov>