Yes, this is possible. The steps are:
1. backup files from volume `/dev/vgmint/volume`
2. unmount it `umount /dev/vgmint/volume`
3. remove logical volume `lvremove /dev/vgmint/volume`
4. extend the volume and filesystem `lvextend --resizefs -L+100%FREE /dev/vgmint/root`
5. restore backuped files (if any)

P.S. I am not sure if the last command will work with `xfs`. If not you should (for point 4) first execute `lvextend -L+100%FREE /dev/vgmint/root` and then `xfs_grow /dev/vgmint/root`