Set "not found" value for svnversion to not-found. Fixes #1463559.
diff --git a/configure.in b/configure.in
index a8b91d6..12ac149 100644
--- a/configure.in
+++ b/configure.in
@@ -621,7 +621,7 @@
 AC_CHECK_PROGS(AR, ar aal, ar)
 
 AC_SUBST(SVNVERSION)
-AC_CHECK_PROG(SVNVERSION, svnversion, found)
+AC_CHECK_PROG(SVNVERSION, svnversion, found, not-found)
 if test $SVNVERSION = found
 then
 	SVNVERSION="svnversion \$(srcdir)"