cache_req: no refresh with CACHE_REQ_BYPASS_PROVIDER
This patch fixes an unexpected behavior of the cache request code if the
CACHE_REQ_BYPASS_PROVIDER option is used. Currently even if this option
is used an expired entry in the cache is refreshed by calling the
provider. With this patch an error is returned if the entry is expired
and the provider is not called.
Reviewed-by: Pavel Březina <firstname.lastname@example.org>