macaroons: ensure path for macaroon DB exists
macaroons: ensure path for macaroon DB exists

Co-Authored-By: Karl Ranna <4c8060af93345c2cc416ee6aa55bceec4e5cc9d4@karlranna.com>

LightningNetwork/lnd,aakselrod/lnd,aakselrod/lnd,LightningNetwork/lnd