Add some checkpoint and redo LSNs to a couple of recovery errors

Add some checkpoint and redo LSNs to a couple of recovery errors

Two FATALs and one PANIC gain details about the LSNs they fail at:
- When restoring from a backup_label, the FATAL log generated when not
finding the checkpoint record now reports its LSN.
- When restoring from a backup_label, the FATAL log generated when not
finding the redo record referenced by a checkpoint record now shows both
the redo and checkpoint record LSNs.
- When not restoring from a backup_label, the PANIC error generated when
not finding the checkpoint record now reports its LSN.

This information is useful when debugging corruption issues, and these
LSNs may not show up in the logs depending on the level of logging
configured in the backend.

Author: David Steele
Discussion: https://postgr.es/m/0e90da89-77ca-4ccf-872c-9626d755e288@pgmasters.net