Initialize errstr in bson_empty
Initialize errstr in bson_empty

It seems like bson_empty should work even without first calling bson_init. Without this fix errstr is set to garbage in that case.

HeliumProject/mongo-c,HeliumProject/mongo-c,Elastica/mongo-c-driver-legacy,Elastica/mongo-c-driver-legacy,mongodb/mongo-c-driver-legacy,Elastica/mongo-c-driver-legacy,HeliumProject/mongo-c,HeliumProject/mongo-c,mongodb/mongo-c-driver-legacy,mongodb/mongo-c-driver-legacy,Elastica/mongo-c-driver-legacy,mongodb/mongo-c-driver-legacy