coding style: fix yield used as a function

doc/gendoc.py

@@ -40,7 +40,7 b' def get_opts(opts):'
         if longopt:
             allopts.append("--%s" % longopt)
         desc += default and _(" (default: %s)") % default or ""
-        yield(", ".join(allopts), desc)
+        yield (", ".join(allopts), desc)
 
 def get_cmd(cmd, cmdtable):
     d = {}

tests/test-check-code.t

@@ -34,7 +34,7 b''
    gratuitous whitespace in () or []
   ./wrong.py:2:
    >     del(arg2)
-   del isn't a function
+   Python keyword is not a function
   ./wrong.py:3:
    >     return ( 5+6, 9)
    missing whitespace in expression