network/smb/server should not be in live image
I don't think we really want either the NFS server or the SMB server in the "live" image.
I discovered that the SMB server is there today when I booted the live image to do some repairs, and when I imported my zpool, the live system tried to start SMB shares...
That's really not desirable.
So, we can avoid this, and save some space, by simply not including the
package pkg:/service/file-system/smb in the live image.