[COMMIT seastar master] util/concepts: include <concepts>

[Commit Bot]

From: Kefu Chai <kefu...@scylladb.com>
Committer: Pavel Emelyanov <xe...@scylladb.com>
Branch: master

util/concepts: include <concepts>

as we always use concepts.hh along with <concepts>, and the former is
pratically a stand-in of the latter. let's just include <concepts>
in util/concepts.hh.

Signed-off-by: Kefu Chai <kefu...@scylladb.com>

Closes #1458

---
diff --git a/include/seastar/util/concepts.hh b/include/seastar/util/concepts.hh
--- a/include/seastar/util/concepts.hh
+++ b/include/seastar/util/concepts.hh
@@ -20,6 +20,10 @@
*/
#pragma once

+#if __has_include(<concepts>)
+#include <concepts>
+#endif
+
#if defined(__cpp_concepts) && __cpp_concepts >= 201907 && \
defined(__cpp_lib_concepts) && __cpp_lib_concepts >= 201907