Fix Id type for GeneralSign (#231)

Author: frodrigo

xsd/netex_part_1/part1_ifopt/netex_ifopt_equipmentSigns_version.xsd

@@ -361,7 +361,7 @@ Rail transport, Roads and Road transport
 							<xsd:group ref="GeneralSignGroup"/>
 						</xsd:sequence>
 					</xsd:sequence>
-					<xsd:attribute name="id" type="HeadingSignIdType" use="optional">
+					<xsd:attribute name="id" type="GeneralSignIdType" use="optional">
 						<xsd:annotation>
 							<xsd:documentation>Identifier of ENTITY.</xsd:documentation>
 						</xsd:annotation>