v2 endpoints: internal & admin protocols support

Allow to change HTTP as default endpoint protocol for both admin &
internal.

Change-Id: I6c724229f35464be681fefb067abe44a86ce84b3
Signed-off-by: Emilien Macchi <emilien.macchi@enovance.com>
(cherry picked from commit 9b33d7e1a7b88109e2b85c281534450bc6e53998)