Add menu configurable long-press function for MENU button

ui/menu.c

@@ -70,6 +70,7 @@ const t_menu_item MenuList[] =
 	{"F1Long",    VOICE_ID_INVALID,                    MENU_F1LONG        },
 	{"F2Shrt",    VOICE_ID_INVALID,                    MENU_F2SHRT        },
 	{"F2Long",    VOICE_ID_INVALID,                    MENU_F2LONG        },
+	{"M Long",    VOICE_ID_INVALID,                    MENU_MLONG         },
 
 	{"KeyLck", VOICE_ID_INVALID,                       MENU_AUTOLK        }, // was "AUTOLk"
 	{"TxTOut", VOICE_ID_TRANSMIT_OVER_TIME,            MENU_TOT           }, // was "TOT"
@@ -834,6 +835,7 @@ void UI_DisplayMenu(void)
 		case MENU_F1LONG:
 		case MENU_F2SHRT:
 		case MENU_F2LONG:
+		case MENU_MLONG:
 			strcpy(String, gSubMenu_SIDEFUNCTIONS[gSubMenuSelection].name);
 			break;