[libc++] Bump `__cpp_lib_constexpr_algorithms` for P2562R1 in C++26 (#132075)
Completes P2562R1.
diff --git a/libcxx/docs/FeatureTestMacroTable.rst b/libcxx/docs/FeatureTestMacroTable.rst
index dcf9838..bbcc76b 100644
--- a/libcxx/docs/FeatureTestMacroTable.rst
+++ b/libcxx/docs/FeatureTestMacroTable.rst
@@ -416,6 +416,8 @@
---------------------------------------------------------- -----------------
``__cpp_lib_bitset`` ``202306L``
---------------------------------------------------------- -----------------
+ ``__cpp_lib_constexpr_algorithms`` ``202306L``
+ ---------------------------------------------------------- -----------------
``__cpp_lib_constexpr_new`` ``202406L``
---------------------------------------------------------- -----------------
``__cpp_lib_constrained_equality`` *unimplemented*
