[vte] sixel: Remove pre-C++20 kludge

[Christian Persch <chpe src gnome org>]

commit 8cff71ef975f5627d1c2201d0ace6d1c08273537
Author: Christian Persch <chpe src gnome org>
Date:   Wed Feb 24 20:27:47 2021 +0100

    sixel: Remove pre-C++20 kludge

 src/sixel-context.hh | 15 +--------------
 1 file changed, 1 insertion(+), 14 deletions(-)
---
diff --git a/src/sixel-context.hh b/src/sixel-context.hh
index 8990748c..75232eff 100644
--- a/src/sixel-context.hh
+++ b/src/sixel-context.hh
@@ -17,6 +17,7 @@
 
 #pragma once
 
+#include <bit>
 #include <cstdint>
 #include <iterator>
 #include <utility>
@@ -31,20 +32,6 @@
 #include "sixel-parser.hh"
 #include "vtedefines.hh"
 
-#if __cplusplus <= 201703L
-// FIXMEchpe remove this and just upgrade to C++20
-namespace std {
-enum class endian
-{
-    little = __ORDER_LITTLE_ENDIAN__,
-    big    = __ORDER_BIG_ENDIAN__,
-    native = __BYTE_ORDER__
-};
-} // namespace std
-#else
-#include <bit>
-#endif
-
 namespace vte::sixel {
 
 class Context {