bitbake: toaster: Replace references to LayerSource models

Replace references to the now deprecated layersource models across
Toaster with the new enums for layer source types.

(Bitbake rev: 48c09c62eb979d840132e58144f0d81ffee675b1)

Signed-off-by: Michael Wood <michael.g.wood@intel.com>
Signed-off-by: Elliot Smith <elliot.smith@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

bitbake/lib/toaster/tests/browser/test_layerdetails_page.py

@@ -49,9 +49,6 @@ class TestLayerDetailsPage(SeleniumTestCase):
         # project to add new custom images to
         self.project = Project.objects.create(name='foo', release=release)
 
-        layer_source = LayerSource.objects.create(
-            sourcetype=LayerSource.TYPE_IMPORTED)
-
         name = "meta-imported"
         vcs_url = "git://example.com/meta-imported"
         subdir = "/layer"