Bump priv spec version and add AsciiDoc note to changelog

src/priv-preface.adoc

@@ -2,7 +2,7 @@
 = Preface
 
 This document describes the RISC-V privileged architecture. This
-release, version 20211203, contains the following versions of the RISC-V ISA
+release, version 20240126, contains the following versions of the RISC-V ISA
 modules:
 
 [%autowidth,float="center",align="center",cols="^,<,^",options="header",]
@@ -34,6 +34,7 @@ _Draft_ +
 The following compatible changes have been made to the Machine ISA since
 version 1.12:
 
+* Transliterated the document from LaTeX into AsciiDoc.
 * Defined the `misa`.V field to reflect that the V extension has been
 implemented.
 * Defined the RV32-only `medelegh` and `hedelegh` CSRs.