rt2x00: Rename config_preamble() to config_erp()

Rename config_preamble() to config_erp() and cleanup argument
list by putting it all into a single structure.
This will make the function more meaningful and easier to
expand later. This second option is mostly intended to make
the patch "mac80211: proper short-slot handling" from Johannes Berg
easier to apply for rt2x00.

Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/rt2x00/rt2x00dev.c b/drivers/net/wireless/rt2x00/rt2x00dev.c
index 455d076..d6b1278 100644
--- a/drivers/net/wireless/rt2x00/rt2x00dev.c
+++ b/drivers/net/wireless/rt2x00/rt2x00dev.c
@@ -447,9 +447,8 @@
 		}
 	}
 
-	if (delayed_flags & DELAYED_CONFIG_PREAMBLE)
-		rt2x00lib_config_preamble(rt2x00dev, intf,
-					  intf->conf.use_short_preamble);
+	if (delayed_flags & DELAYED_CONFIG_ERP)
+		rt2x00lib_config_erp(rt2x00dev, intf, &intf->conf);
 }
 
 static void rt2x00lib_intf_scheduled(struct work_struct *work)