tdf#125636 (part) GPG siging works only for ODF

https://bugs.documentfoundation.org/show_bug.cgi?id=125636#c16

Change-Id: If8826fd96288ac85197a2b937b5e4fdcda528d11
Reviewed-on: https://gerrit.libreoffice.org/c/help/+/122150
Tested-by: Jenkins
Reviewed-by: Olivier Hallot <olivier.hallot@libreoffice.org>
diff --git a/source/text/shared/guide/openpgp.xhp b/source/text/shared/guide/openpgp.xhp
index 515569b..f53e4e7 100644
--- a/source/text/shared/guide/openpgp.xhp
+++ b/source/text/shared/guide/openpgp.xhp
@@ -27,6 +27,8 @@
        <h1 id="hd_id131543693200115"><variable id="openpgph1"><link href="text/shared/guide/openpgp.xhp" name="openpgp">Encrypting Documents with OpenPGP</link></variable></h1>
        <paragraph id="par_id531543693200117" role="paragraph" xml-lang="en-US"><ahelp hid=".">%PRODUCTNAME can encrypt documents using OpenPGP public key cryptography. The document is encrypted using a symmetric encryption algorithm.</ahelp></paragraph>
    </section>
    <comment>According to https://bugs.documentfoundation.org/show_bug.cgi?id=125636#c16 , only ODF files can be signed with GPG</comment>
    <note id="par_id291631706320606">GPG signing only works for ODF documents.</note>
    <section id="howtoget">
        <paragraph role="paragraph" id="par_id551543694091730" xml-lang="en-US">Choose menu <menuitem>File - Save as</menuitem>, select <widget>Encrypt with GPG key</widget>, Click <widget>Save</widget>.</paragraph>
    </section>