util: Add non-family isValidIP

Change-Id: Ib039658d466c0b10b6bc3d1dde9bf5926a124c65
Signed-off-by: William A. Kennington III <wak@google.com>
diff --git a/src/util.hpp b/src/util.hpp
index 52abfb7..16dca64 100644
--- a/src/util.hpp
+++ b/src/util.hpp
@@ -131,6 +131,7 @@
  * @returns true if it is valid otherwise false.
  */
 bool isValidIP(int family, stdplus::const_zstring address) noexcept;
+bool isValidIP(stdplus::const_zstring address) noexcept;
 
 /* @brief checks that the given prefix is valid or not.
  * @param[in] family - IP address family(AF_INET/AF_INET6).