Fix aclocal warning:
/usr/share/aclocal/ksba.m4:17: warning: underquoted definition of AM_PATH_KSBA
--- libksba-0.9.8/src/ksba.m4
+++ libksba-0.9.8/src/ksba.m4
@@ -16,3 +16,3 @@
 dnl
-AC_DEFUN(AM_PATH_KSBA,
+AC_DEFUN([AM_PATH_KSBA],
 [ AC_ARG_WITH(ksba-prefix,