Ipv4NetworkConfigurator: make generateUniqueHostAddress const

Add const qualifier to method and parameters to improve code safety
and indicate that the method doesn't modify object state.

Author: ZoltanBojthe

src/inet/networklayer/configurator/ipv4/Ipv4NetworkConfigurator.cc

@@ -505,7 +505,7 @@ void Ipv4NetworkConfigurator::assignAddresses(Topology& topology)
         assignAddresses(topology.linkInfos);
 }
 
-uint32_t Ipv4NetworkConfigurator::generateUniqueHostAddress(InterfaceInfo *compatibleInterface, uint32_t networkAddress, uint32_t networkNetmask, std::vector<uint32_t> &assignedInterfaceAddresses)
+uint32_t Ipv4NetworkConfigurator::generateUniqueHostAddress(const InterfaceInfo *compatibleInterface, uint32_t networkAddress, uint32_t networkNetmask, const std::vector<uint32_t> &assignedInterfaceAddresses) const
 {
     uint32_t interfaceAddress = compatibleInterface->address & ~networkNetmask;
     uint32_t interfaceAddressSpecifiedBits = compatibleInterface->addressSpecifiedBits;

src/inet/networklayer/configurator/ipv4/Ipv4NetworkConfigurator.h

@@ -236,7 +236,7 @@ class INET_API Ipv4NetworkConfigurator : public L3NetworkConfiguratorBase, publi
 
     // helpers for address assignment
     static bool compareInterfaceInfos(InterfaceInfo *i, InterfaceInfo *j);
-    uint32_t generateUniqueHostAddress(InterfaceInfo *compatibleInterface, uint32_t networkAddress, uint32_t networkNetmask, std::vector<uint32_t> &assignedInterfaceAddresses);
+    uint32_t generateUniqueHostAddress(const InterfaceInfo *compatibleInterface, uint32_t networkAddress, uint32_t networkNetmask, const std::vector<uint32_t> &assignedInterfaceAddresses) const;
     void collectCompatibleInterfaces(const std::vector<InterfaceInfo *>& interfaces, /*in*/
             std::vector<InterfaceInfo *>& compatibleInterfaces, /*out, and the rest too*/
             uint32_t& mergedAddress, uint32_t& mergedAddressSpecifiedBits, uint32_t& mergedAddressIncompatibleBits,