osdmaptool is not mapping child pgs to the target OSDs
Step to reproduce the issue:
1. ceph osd getmap > osdmap.bin
2. ./bin/osdmaptool --test-map-pgs-dump --pool <pool id> --pg_num <current pg number> ../../osdmap.out
3. Choose a new pg number which equals to (current_pg_number * 2) and run step 2 again,
And you'll find the new child PGs are still staying at the exact same OSD with the parent PGs
The reason is that we didn't update the pgp_num which is needed for crush to remap those child PGs.
I believe the user's expectation of this test-map-pgs-dump command should be able to dump the final PG distribution.