Remove configure.in->configure rule (we might not have autoconf).

Makefile.in

diff --git a/Makefile.in b/Makefile.in
index 3c8de43..eaad101 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -237,8 +237,9 @@
 	$(RM) config.* Make.rules include/config.h
 	$(RM) `find . \( -name Makefile -o -size 0 \) -print`
 
-configure: configure.in
-	autoconf
+# We depend on configure above for checks, so we better don't use this rule.
+#configure: configure.in
+#	autoconf
 
 include/config.h.in: configure.in include/acconfig.h
 	autoheader -l include