Fix another portability issue in pg_basebackup.
Fix another portability issue in pg_basebackup.

The target of sscanf with a %o format had better be of integer width,
but "mode_t" conceivably isn't that.  Another compiler warning seen
only on some platforms; this one I think is potentially a real bug
and not just a warning.

kmjungersen/PostgresXL,ashwinstar/gpdb,adam8157/gpdb,zeroae/postgres-xl,yazun/postgres-xl,adam8157/gpdb,50wu/gpdb,ashwinstar/gpdb,snaga/postgres-xl,ovr/postgres-xl,greenplum-db/gpdb,ashwinstar/gpdb,greenplum-db/gpdb,arcivanov/postgres-xl,adam8157/gpdb,postmind-net/postgres-xl,pavanvd/postgres-xl,tpostgres-projects/tPostgres,50wu/gpdb,greenplum-db/gpdb,greenplum-db/gpdb,xinzweb/gpdb,50wu/gpdb,pavanvd/postgres-xl,greenplum-db/gpdb,yazun/postgres-xl,jmcatamney/gpdb,pavanvd/postgres-xl,Postgres-XL/Postgres-XL,50wu/gpdb,ashwinstar/gpdb,greenplum-db/gpdb,yazun/postgres-xl,yazun/postgres-xl,postmind-net/postgres-xl,jmcatamney/gpdb,Postgres-XL/Postgres-XL,kmjungersen/PostgresXL,oberstet/postgres-xl,snaga/postgres-xl,snaga/postgres-xl,adam8157/gpdb,xinzweb/gpdb,jmcatamney/gpdb,ashwinstar/gpdb,lisakowen/gpdb,xinzweb/gpdb,techdragon/Postgres-XL,lisakowen/gpdb,adam8157/gpdb,arcivanov/postgres-xl,50wu/gpdb,techdragon/Postgres-XL,jmcatamney/gpdb,yazun/postgres-xl,lisakowen/gpdb,Postgres-XL/Postgres-XL,lisakowen/gpdb,xinzweb/gpdb,tpostgres-projects/tPostgres,tpostgres-projects/tPostgres,techdragon/Postgres-XL,pavanvd/postgres-xl,xinzweb/gpdb,pavanvd/postgres-xl,lisakowen/gpdb,ovr/postgres-xl,oberstet/postgres-xl,arcivanov/postgres-xl,snaga/postgres-xl,ashwinstar/gpdb,kmjungersen/PostgresXL,lisakowen/gpdb,adam8157/gpdb,oberstet/postgres-xl,50wu/gpdb,ashwinstar/gpdb,postmind-net/postgres-xl,Postgres-XL/Postgres-XL,50wu/gpdb,techdragon/Postgres-XL,lisakowen/gpdb,postmind-net/postgres-xl,snaga/postgres-xl,ovr/postgres-xl,adam8157/gpdb,tpostgres-projects/tPostgres,ovr/postgres-xl,greenplum-db/gpdb,xinzweb/gpdb,zeroae/postgres-xl,xinzweb/gpdb,50wu/gpdb,tpostgres-projects/tPostgres,zeroae/postgres-xl,adam8157/gpdb,jmcatamney/gpdb,Postgres-XL/Postgres-XL,zeroae/postgres-xl,zeroae/postgres-xl,xinzweb/gpdb,ashwinstar/gpdb,techdragon/Postgres-XL,postmind-net/postgres-xl,lisakowen/gpdb,arcivanov/postgres-xl,arcivanov/postgres-xl,oberstet/postgres-xl,jmcatamney/gpdb,arcivanov/postgres-xl,greenplum-db/gpdb,ovr/postgres-xl,jmcatamney/gpdb,kmjungersen/PostgresXL,oberstet/postgres-xl,kmjungersen/PostgresXL,jmcatamney/gpdb