move back to editable install for oslo

Now that we don't have namespace packages any more, editable installs
should be fine. This also means that we apply constraints to these
libraries during installation, which is important for future testing.

This is needed in order to be able to easily sanity check
LIBS_FROM_GIT, as then all libs installed from git will have pip urls
with git in them.

Change-Id: I46c3b8f943b97f912eccc7278e3e033ae67e7e31

lib/infra

@@ -41,7 +41,7 @@ function install_infra {
     # Install pbr
     if use_library_from_git "pbr"; then
         git_clone_by_name "pbr"
-        setup_lib "pbr"
+        setup_dev_lib "pbr"
     else
         # Always upgrade pbr to latest version as we may have pulled it
         # in via system packages.

lib/oslo

@@ -59,7 +59,7 @@ function _do_install_oslo_lib {
     local name=$1
     if use_library_from_git "$name"; then
         git_clone_by_name "$name"
-        setup_lib "$name"
+        setup_dev_lib "$name"
     fi
 }