bitbake: fetch2: Improve mirror building function error handling

First, when building mirror urls we don't do any fetching so we should never
be calling clean functions.

Currently, if a mirror url fails, we don't process it further to see
if there are any mirrors of the mirror.

We should do this even when the mirror url fails, else we may miss out
on valid/useful mappings, particularly in the case of file:// urls.

(Bitbake rev: b7fd3ec9994f664b17fc86423e6e7afac07e897b)

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

bitbake/lib/bb/fetch2/__init__.py

@@ -876,7 +876,9 @@ def build_mirroruris(origud, mirrors, ld):
                 logger.debug(1, "Mirror fetch failure for url %s (original url: %s)" % (newuri, origud.url))
                 logger.debug(1, str(e))
                 try:
-                    ud.method.clean(ud, ld)
+                    # setup_localpath of file:// urls may fail, we should still see 
+                    # if mirrors of the url exist
+                    adduri(newud, uris, uds)
                 except UnboundLocalError:
                     pass
                 continue