Fix the error spotted by meson

- This commit would fix the error that are spotted by meson
  when werror=true is enforced.

Tested By:

- Compiled in all the sdks, and unit tests are passed.

Signed-off-by: Manojkiran Eda <manojkiran.eda@gmail.com>
Change-Id: Ie4c2f26af2b62b019e908cceea18cf22cf2e4607
diff --git a/ipaddress.cpp b/ipaddress.cpp
index 10a22b2..f30cf34 100644
--- a/ipaddress.cpp
+++ b/ipaddress.cpp
@@ -35,23 +35,23 @@
     // Emit deferred signal.
     emit_object_added();
 }
-std::string IPAddress::address(std::string ipAddress)
+std::string IPAddress::address(std::string /*ipAddress*/)
 {
     elog<NotAllowed>(Reason("Property update is not allowed"));
 }
-uint8_t IPAddress::prefixLength(uint8_t value)
+uint8_t IPAddress::prefixLength(uint8_t /*value*/)
 {
     elog<NotAllowed>(Reason("Property update is not allowed"));
 }
-std::string IPAddress::gateway(std::string gateway)
+std::string IPAddress::gateway(std::string /*gateway*/)
 {
     elog<NotAllowed>(Reason("Property update is not allowed"));
 }
-IP::Protocol IPAddress::type(IP::Protocol type)
+IP::Protocol IPAddress::type(IP::Protocol /*type*/)
 {
     elog<NotAllowed>(Reason("Property update is not allowed"));
 }
-IP::AddressOrigin IPAddress::origin(IP::AddressOrigin origin)
+IP::AddressOrigin IPAddress::origin(IP::AddressOrigin /*origin*/)
 {
     elog<NotAllowed>(Reason("Property update is not allowed"));
 }