sstring: add static_assert to prevent use on >1 byte types
sstring: add static_assert to prevent use on >1 byte types

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