add note regarding new Eagle 5.2 image for NXP patch

Change-Id: I40503edf5f9526a448f994c02382214d9b5c4576

Releases.md

diff --git a/Releases.md b/Releases.md
index efeac7e..d2b6da3 100644
--- a/Releases.md
+++ b/Releases.md
@@ -20,6 +20,10 @@
     +   i2s: Enable I2S output on 40-pin header
     +   rt5645: Add a sysfs-based override for hp-detect
 
+**Updated June 2021:** We released a new Mendel 5.2 image for the Coral
+Dev Board and SoM (file version `20210518200035`) that includes a critical
+patch for the NXP SoC. (Does not apply to the Dev Board Mini.)
+
 
 ## 5.0 (eagle)