For survival mode, did they add more beds?

If they have, I certainly haven't noticed.

By the time the new survival mode had come out, I had already made a character with the express intention of exploring every building in the Commonwealth. I didn't have a checklist to work with, but I completed that goal to my satisfaction prior to starting Survival mode.

I have not noticed any new beds anywhere.

That being said, there really are quite a few beds around, and you can always make some in a nearby settlement. As long as you don't mind losing your adrenaline, you can usually find a bed to sleep in fairly near your goal.

To illustrate this, Vemonus has provided a link to a Reddit thread that shows the locations of all the beds in the Commonwealth. I can't independently verify that this is 100% accurate, but it gives you a pretty good idea of how common they really are.