osd: fix PG::all_unfound_are_queried_or_lost for non-existent osds

osd: fix PG::all_unfound_are_queried_or_lost for non-existent osds

A common mistake upon osd loss is to remove the osd from the crush map
before marking the osd lost. This tends to make it so that the user
can no longer mark the osd lost to satisfy all_unfound_are_queried_or_lost.

The simple solution is for all_unfound_are_queried_or_lost to ignore
the osd if it does not exist.

Fixes: #10976
Backports: firefly,giant

Signed-off-by: Mykola Golub <mgolub@mirantis.com>