util: Add a function for converting IP bytes to strings

We need this for future work which turns netlink data into IP addresses.

Tested:
    Run through unit tests.

Change-Id: If078b28246509ca2ebd3bf7bab652b84258df0bd
Signed-off-by: William A. Kennington III <wak@google.com>
diff --git a/util.hpp b/util.hpp
index e01c744..537c6a0 100644
--- a/util.hpp
+++ b/util.hpp
@@ -93,6 +93,12 @@
  */
 uint8_t toCidr(int addressFamily, const std::string& mask);
 
+/* @brief converts the ip bytes into a string representation
+ * @param[in] addr - input ip address to convert.
+ * @returns String representation of the ip.
+ */
+std::string toString(const InAddrAny& addr);
+
 /* @brief converts the prefix into subnetmask.
  * @param[in] addressFamily - IP address family(AF_INET/AF_INET6).
  * @param[in] prefix - prefix length.