build: Remove GNU-make extensions from doc/Makefile.

diff --git a/doc/Makefile.am b/doc/Makefile.am
index 28c3d2c..baf94f3 100644 (file)
--- a/doc/Makefile.am
+++ b/doc/Makefile.am
@@ -5,14 +5,15 @@ dist_man1_MANS =      callcgi.1 dirplex.1 htparser.1 patplex.1 sendfile.1 \
 
 dist_man7_MANS = ashd.7
 
-%.7 %.1: %.doc
+.doc.1:
        a2x -f manpage $<
-
-%.html: %.doc
+.doc.7:
+       a2x -f manpage $<
+.doc.html:
        a2x -f xhtml $<
 
 manpages: $(dist_man1_MANS) $(dist_man7_MANS)
 
-htmldoc: $(patsubst %.doc, %.html, *.doc)
+htmldoc: ${dist_man1_MANS:.1=.html} ${dist_man7_MANS:.7=.html}
 
 EXTRA_DIST = *.doc