Add missing function prototypes to stifle gcc warnings.
Add missing function prototypes to stifle gcc warnings.

snaga/postgres-xl,atris/gpdb,snaga/postgres-xl,tangp3/gpdb,arcivanov/postgres-xl,CraigHarris/gpdb,jmcatamney/gpdb,tpostgres-projects/tPostgres,cjcjameson/gpdb,chrishajas/gpdb,yazun/postgres-xl,tangp3/gpdb,randomtask1155/gpdb,yuanzhao/gpdb,xuegang/gpdb,janebeckman/gpdb,zeroae/postgres-xl,zeroae/postgres-xl,ashwinstar/gpdb,tangp3/gpdb,tangp3/gpdb,edespino/gpdb,tpostgres-projects/tPostgres,Chibin/gpdb,rvs/gpdb,greenplum-db/gpdb,50wu/gpdb,Chibin/gpdb,0x0FFF/gpdb,cjcjameson/gpdb,ashwinstar/gpdb,xuegang/gpdb,pavanvd/postgres-xl,rubikloud/gpdb,xinzweb/gpdb,Quikling/gpdb,rvs/gpdb,arcivanov/postgres-xl,ahachete/gpdb,Quikling/gpdb,rubikloud/gpdb,lisakowen/gpdb,pavanvd/postgres-xl,lintzc/gpdb,lisakowen/gpdb,jmcatamney/gpdb,Postgres-XL/Postgres-XL,greenplum-db/gpdb,edespino/gpdb,lisakowen/gpdb,0x0FFF/gpdb,0x0FFF/gpdb,zaksoup/gpdb,rubikloud/gpdb,ahachete/gpdb,edespino/gpdb,atris/gpdb,50wu/gpdb,arcivanov/postgres-xl,adam8157/gpdb,arcivanov/postgres-xl,rvs/gpdb,xuegang/gpdb,lisakowen/gpdb,Quikling/gpdb,snaga/postgres-xl,cjcjameson/gpdb,royc1/gpdb,janebeckman/gpdb,chrishajas/gpdb,kaknikhil/gpdb,jmcatamney/gpdb,foyzur/gpdb,adam8157/gpdb,lisakowen/gpdb,ahachete/gpdb,royc1/gpdb,ashwinstar/gpdb,CraigHarris/gpdb,ashwinstar/gpdb,randomtask1155/gpdb,kmjungersen/PostgresXL,Chibin/gpdb,Quikling/gpdb,tangp3/gpdb,rubikloud/gpdb,atris/gpdb,rvs/gpdb,ashwinstar/gpdb,adam8157/gpdb,adam8157/gpdb,yuanzhao/gpdb,oberstet/postgres-xl,royc1/gpdb,xinzweb/gpdb,yuanzhao/gpdb,0x0FFF/gpdb,royc1/gpdb,cjcjameson/gpdb,randomtask1155/gpdb,techdragon/Postgres-XL,cjcjameson/gpdb,lpetrov-pivotal/gpdb,lisakowen/gpdb,rubikloud/gpdb,50wu/gpdb,kaknikhil/gpdb,lisakowen/gpdb,royc1/gpdb,greenplum-db/gpdb,snaga/postgres-xl,Quikling/gpdb,lintzc/gpdb,edespino/gpdb,CraigHarris/gpdb,chrishajas/gpdb,zaksoup/gpdb,atris/gpdb,rvs/gpdb,lintzc/gpdb,Postgres-XL/Postgres-XL,jmcatamney/gpdb,tangp3/gpdb,ahachete/gpdb,chrishajas/gpdb,oberstet/postgres-xl,lpetrov-pivotal/gpdb,yazun/postgres-xl,arcivanov/postgres-xl,lintzc/gpdb,janebeckman/gpdb,50wu/gpdb,xinzweb/gpdb,foyzur/gpdb,janebeckman/gpdb,randomtask1155/gpdb,foyzur/gpdb,ashwinstar/gpdb,randomtask1155/gpdb,ovr/postgres-xl,ovr/postgres-xl,chrishajas/gpdb,yuanzhao/gpdb,CraigHarris/gpdb,rvs/gpdb,xinzweb/gpdb,xinzweb/gpdb,yuanzhao/gpdb,adam8157/gpdb,postmind-net/postgres-xl,foyzur/gpdb,rvs/gpdb,janebeckman/gpdb,oberstet/postgres-xl,xinzweb/gpdb,foyzur/gpdb,lintzc/gpdb,yazun/postgres-xl,yuanzhao/gpdb,yuanzhao/gpdb,postmind-net/postgres-xl,kmjungersen/PostgresXL,jmcatamney/gpdb,Postgres-XL/Postgres-XL,cjcjameson/gpdb,kaknikhil/gpdb,zaksoup/gpdb,lpetrov-pivotal/gpdb,pavanvd/postgres-xl,zeroae/postgres-xl,chrishajas/gpdb,jmcatamney/gpdb,rvs/gpdb,yuanzhao/gpdb,techdragon/Postgres-XL,ahachete/gpdb,postmind-net/postgres-xl,greenplum-db/gpdb,postmind-net/postgres-xl,CraigHarris/gpdb,rubikloud/gpdb,zaksoup/gpdb,Chibin/gpdb,50wu/gpdb,chrishajas/gpdb,techdragon/Postgres-XL,rubikloud/gpdb,cjcjameson/gpdb,zaksoup/gpdb,Chibin/gpdb,xuegang/gpdb,edespino/gpdb,randomtask1155/gpdb,yazun/postgres-xl,zeroae/postgres-xl,lpetrov-pivotal/gpdb,kaknikhil/gpdb,ovr/postgres-xl,kaknikhil/gpdb,Quikling/gpdb,xuegang/gpdb,cjcjameson/gpdb,janebeckman/gpdb,jmcatamney/gpdb,lintzc/gpdb,lintzc/gpdb,xuegang/gpdb,CraigHarris/gpdb,lintzc/gpdb,foyzur/gpdb,randomtask1155/gpdb,greenplum-db/gpdb,kaknikhil/gpdb,lpetrov-pivotal/gpdb,ashwinstar/gpdb,adam8157/gpdb,ashwinstar/gpdb,foyzur/gpdb,randomtask1155/gpdb,Quikling/gpdb,adam8157/gpdb,edespino/gpdb,jmcatamney/gpdb,greenplum-db/gpdb,zaksoup/gpdb,Chibin/gpdb,tpostgres-projects/tPostgres,adam8157/gpdb,snaga/postgres-xl,janebeckman/gpdb,cjcjameson/gpdb,CraigHarris/gpdb,0x0FFF/gpdb,xuegang/gpdb,50wu/gpdb,kaknikhil/gpdb,cjcjameson/gpdb,0x0FFF/gpdb,ahachete/gpdb,rvs/gpdb,Chibin/gpdb,0x0FFF/gpdb,50wu/gpdb,Chibin/gpdb,yuanzhao/gpdb,ahachete/gpdb,kmjungersen/PostgresXL,CraigHarris/gpdb,Quikling/gpdb,atris/gpdb,ovr/postgres-xl,Postgres-XL/Postgres-XL,rubikloud/gpdb,lpetrov-pivotal/gpdb,pavanvd/postgres-xl,edespino/gpdb,lisakowen/gpdb,atris/gpdb,pavanvd/postgres-xl,xinzweb/gpdb,lintzc/gpdb,ovr/postgres-xl,Quikling/gpdb,tangp3/gpdb,edespino/gpdb,CraigHarris/gpdb,greenplum-db/gpdb,kaknikhil/gpdb,oberstet/postgres-xl,edespino/gpdb,lpetrov-pivotal/gpdb,janebeckman/gpdb,foyzur/gpdb,yuanzhao/gpdb,ahachete/gpdb,chrishajas/gpdb,tangp3/gpdb,janebeckman/gpdb,kaknikhil/gpdb,50wu/gpdb,royc1/gpdb,Postgres-XL/Postgres-XL,arcivanov/postgres-xl,xuegang/gpdb,kmjungersen/PostgresXL,atris/gpdb,Chibin/gpdb,rvs/gpdb,zeroae/postgres-xl,royc1/gpdb,zaksoup/gpdb,techdragon/Postgres-XL,tpostgres-projects/tPostgres,Quikling/gpdb,edespino/gpdb,oberstet/postgres-xl,lpetrov-pivotal/gpdb,Chibin/gpdb,kaknikhil/gpdb,atris/gpdb,xinzweb/gpdb,kmjungersen/PostgresXL,0x0FFF/gpdb,postmind-net/postgres-xl,xuegang/gpdb,greenplum-db/gpdb,yazun/postgres-xl,zaksoup/gpdb,techdragon/Postgres-XL,tpostgres-projects/tPostgres,royc1/gpdb,janebeckman/gpdb