document change in pdfa

Author: u-fischer

doc/hyperref-doc.tex

@@ -2148,7 +2148,7 @@ \subsection{Option `pdfa'}
   the loading of the package and cannot be changed after \xpackage{hyperref} is
   loaded (\verb|\usepackage{hyperref}|).
 
-
+If the PDF management is loaded with \cs{DocumentMetadata} the option is automatically set/unset depending on if an A-standard is set with the `pdfstandard` key. The manual setting of `pdfa` is then ignored. 
 
 \subsection{Option `linktoc' added}