fstream: disable read-ahead for now
fstream: disable read-ahead for now

Allow applications time to catch up with the new API requiring close().

xtao/seastar,wildinto/seastar,shyamalschandra/seastar,norcimo5/seastar,acbellini/seastar,leejir/seastar,dreamsxin/seastar,hongliangzhao/seastar,avikivity/seastar,scylladb/seastar,jonathanleang/seastar,joerg84/seastar,kjniemi/seastar,sjperkins/seastar,dreamsxin/seastar,koolhazz/seastar,koolhazz/seastar,avikivity/seastar,wildinto/seastar,acbellini/seastar,hongliangzhao/seastar,norcimo5/seastar,leejir/seastar,tempbottle/seastar,printedheart/seastar,joerg84/seastar,shyamalschandra/seastar,wildinto/seastar,norcimo5/seastar,bowlofstew/seastar,scylladb/scylla-seastar,kjniemi/seastar,hongliangzhao/seastar,sjperkins/seastar,dwdm/seastar,xtao/seastar,dwdm/seastar,shyamalschandra/seastar,scylladb/scylla-seastar,joerg84/seastar,acbellini/seastar,stamhe/seastar,dwdm/seastar,tempbottle/seastar,anzihenry/seastar,linearregression/seastar,anzihenry/seastar,cloudius-systems/seastar,stamhe/seastar,stamhe/seastar,scylladb/seastar,bowlofstew/seastar,xtao/seastar,linearregression/seastar,printedheart/seastar,printedheart/seastar,kjniemi/seastar,leejir/seastar,koolhazz/seastar,syuu1228/seastar,jonathanleang/seastar,tempbottle/seastar,anzihenry/seastar,chunshengster/seastar,chunshengster/seastar,dreamsxin/seastar,syuu1228/seastar,scylladb/seastar,flashbuckets/seastar,scylladb/scylla-seastar,cloudius-systems/seastar,chunshengster/seastar,jonathanleang/seastar,syuu1228/seastar,flashbuckets/seastar,sjperkins/seastar,bowlofstew/seastar,avikivity/seastar,flashbuckets/seastar,cloudius-systems/seastar,linearregression/seastar