doc: Document AVX2, BMI1, BMI2 and TSX support.

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
diff --git a/doc/changes.src b/doc/changes.src
index 103d5a3..ab6fb52 100644
--- a/doc/changes.src
+++ b/doc/changes.src
@@ -36,6 +36,11 @@
 
 To force a specific form, use the \c{STRICT} keyword, see \k{strict}.
 
+\b Add support for the Intel AVX2 instruction set.
+
+\b Add support for Bit Manipulation Instructions 1 and 2.
+
+\b Add support for Intel Transactional Synchronization Extensions (TSX).
 
 \S{cl-2.09.10} Version 2.09.10