[PATCH synaptics] Fail if no backends can be found

[Peter Hutterer]

Apparently the driver broke on Solaris when the backends were made optional
in cf451f34e3bdd52a4eb072ce9f4b514eb83a1cfc. The driver would still build,
but without backends there it has limited usefulness.

Signed-off-by: Peter Hutterer <peter.hutterer at who-t.net>
---
 configure.ac |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/configure.ac b/configure.ac
index dbf3fec..5c2c25d 100644
--- a/configure.ac
+++ b/configure.ac
@@ -120,7 +120,7 @@ case "${host}" in
 	BUILD_PS2COMM="yes"
 	;;
 *)
-	AC_MSG_RESULT([none])
+	AC_MSG_ERROR("Cannot find suitable backends for this platform.")
 	;;
 esac
 if test "x$BUILD_EVENTCOMM" = xyes; then
-- 
1.7.10