wireguard-go: bump for ARM64 ChaCha20

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

diff --git a/wireguard-go b/wireguard-go
index c4b43e35a772305858e610d879c2b9d47f4d9866..f7170e5de2065f37bac647484b34711db4797394 160000 (submodule)
--- a/wireguard-go
+++ b/wireguard-go
@@ -1 +1 @@
-Subproject commit c4b43e35a772305858e610d879c2b9d47f4d9866
+Subproject commit f7170e5de2065f37bac647484b34711db4797394