file: clarify the class interface.
file: clarify the class interface.

Move read_state helper class, file::dma_read_bulk() and file::read_maybe_eof()
definitions outside the class declaration in order to make reading the class
interface easier.

Signed-off-by: Vlad Zolotarov <976c0f8d0852ed6439ad273880b400a75a7c41d0@cloudius-systems.com>

chunshengster/seastar,justintung/scylla,shyamalschandra/seastar,dreamsxin/seastar,stamhe/scylla,jonathanleang/seastar,koolhazz/seastar,stamhe/seastar,mixja/seastar,norcimo5/seastar,guiquanz/scylla,dreamsxin/seastar,flashbuckets/seastar,koolhazz/seastar,stamhe/scylla,aruanruan/scylla,dwdm/scylla,eklitzke/scylla,duarten/scylla,linearregression/scylla,leejir/seastar,syuu1228/seastar,bowlofstew/scylla,bowlofstew/seastar,kjniemi/seastar,gwicke/scylla,chunshengster/seastar,koolhazz/seastar,bzero/seastar,gwicke/scylla,printedheart/seastar,mixja/seastar,shyamalschandra/seastar,syuu1228/seastar,raphaelsc/scylla,xtao/seastar,capturePointer/scylla,glommer/scylla,scylladb/scylla-seastar,senseb/scylla,justintung/scylla,leejir/seastar,flashbuckets/seastar,senseb/scylla,hongliangzhao/seastar,scylladb/scylla-seastar,acbellini/scylla,shaunstanislaus/scylla,scylladb/scylla,anzihenry/seastar,tempbottle/seastar,cloudius-systems/seastar,wildinto/seastar,asias/scylla,capturePointer/scylla,avikivity/scylla,aruanruan/scylla,rentongzhang/scylla,kjniemi/seastar,phonkee/scylla,raphaelsc/scylla,respu/scylla,linearregression/scylla,wildinto/seastar,bzero/seastar,joerg84/seastar,flashbuckets/seastar,victorbriz/scylla,joerg84/seastar,scylladb/seastar,justintung/scylla,duarten/scylla,shaunstanislaus/scylla,dwdm/seastar,avikivity/seastar,avikivity/scylla,eklitzke/scylla,anzihenry/seastar,syuu1228/seastar,capturePointer/scylla,glommer/scylla,victorbriz/scylla,stamhe/seastar,dwdm/seastar,tempbottle/scylla,victorbriz/scylla,rentongzhang/scylla,duarten/scylla,asias/scylla,scylladb/scylla-seastar,printedheart/seastar,tempbottle/seastar,avikivity/seastar,rluta/scylla,scylladb/seastar,wildinto/scylla,tempbottle/scylla,acbellini/scylla,rluta/scylla,stamhe/scylla,linearregression/seastar,norcimo5/seastar,bowlofstew/scylla,scylladb/scylla,dwdm/scylla,mixja/seastar,tempbottle/scylla,scylladb/scylla,hongliangzhao/seastar,scylladb/scylla,asias/scylla,acbellini/seastar,sjperkins/seastar,sjperkins/seastar,bowlofstew/seastar,kangkot/scylla,xtao/seastar,guiquanz/scylla,linearregression/scylla,glommer/scylla,wildinto/scylla,acbellini/scylla,kjniemi/scylla,stamhe/seastar,tempbottle/seastar,guiquanz/scylla,bzero/seastar,acbellini/seastar,kjniemi/scylla,respu/scylla,acbellini/seastar,kangkot/scylla,avikivity/scylla,leejir/seastar,bowlofstew/seastar,cloudius-systems/seastar,rluta/scylla,dreamsxin/seastar,joerg84/seastar,aruanruan/scylla,respu/scylla,sjperkins/seastar,dwdm/scylla,scylladb/seastar,wildinto/seastar,printedheart/seastar,bowlofstew/scylla,wildinto/scylla,kjniemi/seastar,dwdm/seastar,xtao/seastar,jonathanleang/seastar,chunshengster/seastar,anzihenry/seastar,rentongzhang/scylla,linearregression/seastar,linearregression/seastar,kjniemi/scylla,kangkot/scylla,norcimo5/seastar,hongliangzhao/seastar,jonathanleang/seastar,raphaelsc/scylla,gwicke/scylla,cloudius-systems/seastar,shaunstanislaus/scylla,phonkee/scylla,avikivity/seastar,phonkee/scylla,senseb/scylla,shyamalschandra/seastar,eklitzke/scylla