randv2: link to chacha8rand

Change-Id: I84e919fdaeda92b1be6ab8b269e9e7a0793d3614
Reviewed-on: https://go-review.googlesource.com/c/website/+/582816
Auto-Submit: Russ Cox <rsc@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Peter Weinberger <pjw@google.com>
diff --git a/_content/blog/randv2.md b/_content/blog/randv2.md
index e7e3a7b..4e52d1a 100644
--- a/_content/blog/randv2.md
+++ b/_content/blog/randv2.md
@@ -119,7 +119,7 @@
 We also wanted to explore using
 Daniel J. Bernstein's [ChaCha stream cipher](https://cr.yp.to/chacha.html)
 as a generator.
-A followup post will discuss that generator specifically.
+A [follow-up post](/blog/chacha8rand) discusses that generator specifically.
 
 ### Source Interface {#problem.source}
 
@@ -493,4 +493,4 @@
 ensuring that users who don't migrate from v1 still
 benefit from optimizations and security fixes in v2.
 
-A follow-up blog post will present the `ChaCha8` generator in more detail.
+A [follow-up blog post](/blog/chacha8rand) presents the `ChaCha8` generator in more detail.