warning on compile pg_probackup 13 on RHEL8.3

[shab2]

src/catalog.c: In function ‘lock_backup’:
src/catalog.c:603:9: warning: ‘encoded_pid’ may be used uninitialized in this function [-Wmaybe-uninitialized]
elog(WARNING, "Cannot to lock backup %s in exclusive mode, because process %u owns shared lock",
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
base36enc(backup->start_time), encoded_pid);
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
src/catalog.c:536:11: note: ‘encoded_pid’ was declared here
pid_t encoded_pid;
^~~~~~~~~~~

[gsmolk]

Hello!
Fixed that in 8e930b7