ZVISION: Fix Missing Default Switch Cases

These are flagged by GCC if -Wswitch-default is enabled.

engines/zvision/graphics/render_table.cpp

@@ -63,6 +63,8 @@ void RenderTable::setRenderState(RenderState newState) {
 	case FLAT:
 		// Intentionally left empty
 		break;
+	default:
+		break;
 	}
 }
 
@@ -137,6 +139,8 @@ void RenderTable::generateRenderTable() {
 	case ZVision::RenderTable::FLAT:
 		// Intentionally left empty
 		break;
+	default:
+		break;
 	}
 }
 

engines/zvision/scripting/controls/lever_control.cpp

@@ -360,6 +360,8 @@ int LeverControl::calculateVectorAngle(const Common::Point &pointOne, const Comm
 		case 3:
 			angle = 180 + angle;
 			break;
+		default:
+			break;
 		}
 
 		return angle;

engines/zvision/scripting/menu.cpp

@@ -201,6 +201,9 @@ void MenuZGI::onMouseUp(const Common::Point &Pos) {
 					_engine->getScriptManager()->changeLocation('g', 'j', 's', 'e', 0);
 				}
 			break;
+
+		default:
+			break;
 		}
 	}
 }

engines/zvision/scripting/script_manager.cpp

@@ -245,6 +245,8 @@ bool ScriptManager::checkPuzzleCriteria(Puzzle *puzzle, uint counter) {
 			case Puzzle::LESS_THAN:
 				criteriaMet = getStateValue(entryIter->key) < argumentValue;
 				break;
+			default:
+				break;
 			}
 
 			// If one check returns false, don't keep checking