bitbake: siggen: Add missing error message parameter

There is clearly a missing parameter from this error message, add it.

(Bitbake rev: d98be5ea69b99fb7934fc3093422f139bc37a1cc)

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

bitbake/lib/bb/siggen.py

@@ -24,7 +24,7 @@ def init(d):
             break
     else:
         logger.error("Invalid signature generator '%s', using default 'noop'\n"
-                     "Available generators: %s",
+                     "Available generators: %s", desired,
                      ', '.join(obj.name for obj in siggens))
         return SignatureGenerator(d)