[libc++][PSTL] Implement std::rotate_copy

Reviewed By: #libc, ldionne

Spies: ldionne, libcxx-commits

Differential Revision: https://reviews.llvm.org/D155025
diff --git a/libcxx/include/algorithm b/libcxx/include/algorithm
index ac335cb..7dcf396 100644
--- a/libcxx/include/algorithm
+++ b/libcxx/include/algorithm
@@ -1835,6 +1835,7 @@
 #include <__algorithm/pstl_merge.h>
 #include <__algorithm/pstl_move.h>
 #include <__algorithm/pstl_replace.h>
+#include <__algorithm/pstl_rotate_copy.h>
 #include <__algorithm/pstl_sort.h>
 #include <__algorithm/pstl_stable_sort.h>
 #include <__algorithm/pstl_transform.h>