Update to C++20

Change-Id: Ieeb22ae54e5be9cc8bfa69c3e09f5afd9245da32
Signed-off-by: Jason M. Bills <jason.m.bills@linux.intel.com>
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 694e27d..783d43c 100755
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,6 +1,6 @@
 cmake_minimum_required (VERSION 3.2 FATAL_ERROR)
 include (ExternalProject)
-set (CMAKE_CXX_STANDARD 17)
+set (CMAKE_CXX_STANDARD 20)
 set (CMAKE_CXX_STANDARD_REQUIRED ON)
 set (CMAKE_MODULE_PATH ${CMAKE_CURRENT_SOURCE_DIR}/cmake ${CMAKE_MODULE_PATH})
 set (DBUS_OBJECT_NAME "xyz/openbmc_project/Smbios/MDR_V2")