commitlog: don't specify the default_size in terms of alignment
commitlog: don't specify the default_size in terms of alignment

Use kiB units instead.

respu/scylla,capturePointer/scylla,guiquanz/scylla,asias/scylla,asias/scylla,respu/scylla,gwicke/scylla,avikivity/scylla,rentongzhang/scylla,kjniemi/scylla,victorbriz/scylla,wildinto/scylla,tempbottle/scylla,shaunstanislaus/scylla,kangkot/scylla,stamhe/scylla,bowlofstew/scylla,capturePointer/scylla,senseb/scylla,stamhe/scylla,glommer/scylla,rentongzhang/scylla,avikivity/scylla,glommer/scylla,glommer/scylla,bowlofstew/scylla,wildinto/scylla,rluta/scylla,guiquanz/scylla,aruanruan/scylla,phonkee/scylla,tempbottle/scylla,scylladb/scylla,scylladb/scylla,raphaelsc/scylla,bowlofstew/scylla,avikivity/scylla,victorbriz/scylla,kangkot/scylla,rluta/scylla,capturePointer/scylla,acbellini/scylla,stamhe/scylla,kjniemi/scylla,senseb/scylla,scylladb/scylla,wildinto/scylla,aruanruan/scylla,eklitzke/scylla,duarten/scylla,raphaelsc/scylla,aruanruan/scylla,dwdm/scylla,acbellini/scylla,rentongzhang/scylla,dwdm/scylla,raphaelsc/scylla,victorbriz/scylla,justintung/scylla,rluta/scylla,linearregression/scylla,eklitzke/scylla,justintung/scylla,asias/scylla,kjniemi/scylla,linearregression/scylla,kangkot/scylla,duarten/scylla,duarten/scylla,linearregression/scylla,shaunstanislaus/scylla,tempbottle/scylla,guiquanz/scylla,eklitzke/scylla,scylladb/scylla,respu/scylla,phonkee/scylla,gwicke/scylla,senseb/scylla,gwicke/scylla,shaunstanislaus/scylla,dwdm/scylla,phonkee/scylla,acbellini/scylla,justintung/scylla