Replace strdup() with pstrdup(), to avoid leaking memory.
Replace strdup() with pstrdup(), to avoid leaking memory.

It's been like this since the seg module was introduced, so backpatch to
8.2 which is the oldest supported version.

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