remove redundant if check
remove redundant if check

coverity CID 115892.

beingmeta/mongo-c-driver,jmikola/mongo-c-driver,jmikola/mongo-c-driver,rcsanchez97/mongo-c-driver,beingmeta/mongo-c-driver,rcsanchez97/mongo-c-driver,jmikola/mongo-c-driver,mongodb/mongo-c-driver,beingmeta/mongo-c-driver,rcsanchez97/mongo-c-driver,rcsanchez97/mongo-c-driver,mongodb/mongo-c-driver,jmikola/mongo-c-driver,rcsanchez97/mongo-c-driver,rcsanchez97/mongo-c-driver,jmikola/mongo-c-driver,beingmeta/mongo-c-driver,mongodb/mongo-c-driver,jmikola/mongo-c-driver,mongodb/mongo-c-driver,beingmeta/mongo-c-driver,beingmeta/mongo-c-driver,jmikola/mongo-c-driver,mongodb/mongo-c-driver,rcsanchez97/mongo-c-driver,mongodb/mongo-c-driver,beingmeta/mongo-c-driver,beingmeta/mongo-c-driver,mongodb/mongo-c-driver