awful.rules: Emit request::activate on the client

There is a strong hint that you are doing something wrong: You call
client.emit_signal(some_signal, c). Chances are high that this signal is
supposed to be emitted on the client object 'c' instead of the underlying client
class.

This applies to awful.rules' usage of this signal.

Signed-off-by: Uli Schlachter <psychon@znc.in>

lib/awful/rules.lua.in

@@ -237,7 +237,7 @@ function rules.execute(c, props, callbacks)
     -- Do this at last so we do not erase things done by the focus
     -- signal.
     if props.focus and (type(props.focus) ~= "function" or props.focus(c)) then
-        client.emit_signal('request::activate', c)
+        c:emit_signal('request::activate')
     end
 end