Build failed

@carsten.schoenert build faild on arm02 like:

a2x: ERROR: "xsltproc" --stringparam callout.graphics 0 --stringparam navig.graphics 0 --stringparam admon.textlabel 1 --stringparam admon.graphics 0 "/etc/asciidoc/docbook-xsl/manpage.xsl" "/build/nheko-0.9.3+ds/build/man/nheko.1.xml" returned non-zero exit status 5

see https://lists.community.puri.sm/pipermail/librem5-builds/2022-July/003832.html