docs/releases/4.19: Add toolchain updates

Change-Id: If8c3f8e18ccbec8770917cc97aa562eac7417aaf
Signed-off-by: Elyes Haouas <ehaouas@noos.fr>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/71178
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Jason Glenesk <jason.glenesk@gmail.com>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
diff --git a/Documentation/releases/coreboot-4.19-relnotes.md b/Documentation/releases/coreboot-4.19-relnotes.md
index 213ae63..e4dc0af 100644
--- a/Documentation/releases/coreboot-4.19-relnotes.md
+++ b/Documentation/releases/coreboot-4.19-relnotes.md
@@ -51,6 +51,15 @@
 always has LZMA support included.
 
 
+### Toolchain updates
+
+* Upgrade LLVM from 15.0.0 to 15.0.6
+* Upgrade CMake from 3.24.2 to 3.25.0
+* Upgrade IASL from 20220331 to 20221020
+* Upgrade MPFR from 4.1.0 to 4.1.1
+
+
+
 Additional coreboot changes
 ---------------------------