The kind of licking described is excessive and shows the dog to be anxious and overly attention seeking to ease it's anxiety. By allowing this to continue the puppy would come to rely on the action to feel secure. It is far better to have a secure animal that is confident of its position without the constant need for physical contact and reassurance. The attention seeking aspect is likely to develop in other behaviours if this is not dealt with.
This is not the normal puppy kisses when playing, cuddling or when asked for.
I am allergic to dogs and their saliva especially so I'm not too keen on puppy kisses myself, but there is nothing wrong at all as long as it is under control.