objecter: don't resend linger ops unnecessarily

objecter: don't resend linger ops unnecessarily

recalc_linger_op_target() was checking and then setting
linger_op->pgid and linger_op->active, but these were only set by
recalc_linger_op_target(). This was only called by handle_osd_map(),
so the first osdmap after a watch was established would cause a resend
of the watch. Analogous to the normal Op, set this information by
calling recalc_linger_op_target in send_linger().

Signed-off-by: Josh Durgin <josh.durgin@inktank.com>