Build as c++17

Change-Id: I979a1afd51cb51cc38506a12321bbc4cbab76b8c
Signed-off-by: Patrick Venture <venture@google.com>
diff --git a/configure.ac b/configure.ac
index 267cb5b..bf03958 100644
--- a/configure.ac
+++ b/configure.ac
@@ -17,7 +17,7 @@
 [AC_MSG_ERROR([Could not find python-2.7 installed...python-2.7 is required])])
 
 # Checks for typedefs, structures, and compiler characteristics.
-AX_CXX_COMPILE_STDCXX_14([noext])
+AX_CXX_COMPILE_STDCXX_17([noext])
 AX_APPEND_COMPILE_FLAGS([-fpic -Wall -Werror], [CXXFLAGS])
 
 # Checks for libraries.