Kill unneeded call to AC_PROG_SYSCONFTOOL (bug #168206).

--- a/configure.ac	2022-11-05 19:37:21.629552607 +0100
+++ b/configure.ac	2022-11-05 19:37:31.622405720 +0100
@@ -14,7 +14,6 @@
 AC_PROG_INSTALL
 AC_PROG_LN_S
 AC_PROG_MAKE_SET
-AC_PROG_SYSCONFTOOL
 LT_INIT
 
 AC_PATH_PROGS(PERL, perl5 perl, perl)