git: fixed to build documentation using Asciidoc 8

develop/git/git.conf

@@ -25,6 +25,8 @@ var_append makeinstopt ' ' 'gitwebdir=$root$docdir/gitweb'
 var_append makeinstopt ' ' 'install-gitweb'
 
 if pkginstalled -f asciidoc; then
+	# documentation is written for AsciiDoc 7, but we use Asciidoc 8
+	var_append makeopt ' ' 'ASCIIDOC8=YesPlease'
 	var_append makeopt ' ' 'html'
 	var_append makeinstopt ' ' 'install-html'
 	# build/install man pages