phosphor-led-manager: use c++17

Update configure.ac to choose the c++17 standard

Change-Id: I805dd7d6de5d8be529d48646cec0c815574c281d
Signed-off-by: Vernon Mauery <vernon.mauery@linux.intel.com>
diff --git a/configure.ac b/configure.ac
index ba1a152..f9ddc4b 100644
--- a/configure.ac
+++ b/configure.ac
@@ -12,7 +12,7 @@
 AC_PROG_MAKE_SET
 
 # Checks for typedefs, structures, and compiler characteristics.
-AX_CXX_COMPILE_STDCXX_14([noext])
+AX_CXX_COMPILE_STDCXX_17([noext])
 AX_APPEND_COMPILE_FLAGS([-Wall -Werror], [CXXFLAGS])
 
 # Python