[libc++][ranges] Add indirectly_comparable concept

Add `indirectly_comparable` concept

Reviewed By: Quuxplusone, Mordante, #libc

Spies: mgorny, libcxx-commits

Differential Revision: https://reviews.llvm.org/D116268

NOKEYCHECK=True
GitOrigin-RevId: 6d722801d1a2cd1af8e139c8052443feb62c0eae
diff --git a/include/module.modulemap b/include/module.modulemap
index 1dc6db4..8eba28b 100644
--- a/include/module.modulemap
+++ b/include/module.modulemap
@@ -594,6 +594,7 @@
       module erase_if_container    { private header "__iterator/erase_if_container.h" }
       module front_insert_iterator { private header "__iterator/front_insert_iterator.h" }
       module incrementable_traits  { private header "__iterator/incrementable_traits.h" }
+      module indirectly_comparable { private header "__iterator/indirectly_comparable.h" }
       module insert_iterator       { private header "__iterator/insert_iterator.h" }
       module istream_iterator      { private header "__iterator/istream_iterator.h" }
       module istreambuf_iterator   { private header "__iterator/istreambuf_iterator.h" }