Remove useless '_profile_base_location_' entry from shared signature

The value was always '${:_profile_base_location_}'

slapos/recipe/cmmi/__init__.py

@@ -48,10 +48,12 @@ class Recipe(object):
             buildout_directory = buildout['buildout']['directory']
             profile_base_location = options.get('_profile_base_location_', '')
             for k, v in sorted(options.items()):
-                # Key not vary on profile base location
-                if profile_base_location:
-                    v = v.replace(profile_base_location, '${:_profile_base_location_}')
-                self._signature.update(k, v)
+                if k != '_profile_base_location_':
+                    # Key not vary on profile base location
+                    if profile_base_location:
+                        v = v.replace(profile_base_location,
+                                      '${:_profile_base_location_}')
+                    self._signature.update(k, v)
 
             signature_digest = self._signature.hexdigest()
             for x in shared.splitlines():