Adjust basebackup.c to suppress compiler warnings.
Adjust basebackup.c to suppress compiler warnings.

Some versions of gcc complain about "variable `tablespaces' might be
clobbered by `longjmp' or `vfork'" with the original coding.  Fix by
moving the PG_TRY block into a separate subroutine.

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