Rover: Fix AP_Relay param naming

Author: WickedShell

Rover/Parameters.cpp

@@ -222,9 +222,9 @@ const AP_Param::Info Rover::var_info[] = {
     GOBJECT(barometer, "BARO", AP_Baro),
 
 #if AP_RELAY_ENABLED
-    // @Group: RELAY_
+    // @Group: RELAY
     // @Path: ../libraries/AP_Relay/AP_Relay.cpp
-    GOBJECT(relay,                  "RELAY_", AP_Relay),
+    GOBJECT(relay,                  "RELAY", AP_Relay),
 #endif
 
     // @Group: RCMAP_