Bump BeefBoot to C++17

BeefBoot/CMakeLists.txt

@@ -113,7 +113,7 @@ if(MSVC)
    set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} /W3 /GL /Od /Oi /Gy /EHsc")
 endif(MSVC)
 if(NOT MSVC)
-  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11 -Wno-multichar -Wno-invalid-offsetof")  
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++17 -Wno-multichar -Wno-invalid-offsetof")  
   if ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "Clang")
     #set (CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -stdlib=libc++")
   endif()