Set CE length to 0 in LE_Create_Connection

- Currently the value is set to constant min/max which does not make
  sense to the controller in most of the cases.
- Set length to 0 to align with the behavior in legacy stack as well
  as the extended create connection command in gd stack.

Bug: 268702775
Test: cert/run
Change-Id: Ie6a0aefb9bc35ddc6e6ab4c0aced6c0e860565b5