Move BarberPole from HaikuDepot to libshared

I want to use this in at least 2 third-party applications. I think it's
time to make it shared?

Change-Id: I855a59aab4ad6d47d77cf2901cb3dfc34c108059
Reviewed-on: https://review.haiku-os.org/c/haiku/+/6296
Reviewed-by: waddlesplash <waddlesplash@gmail.com>