Added preferences to dinput drivers (so we can have two joystick
drivers). Implemented a joystick driver for the Linux 2.4
dev/input/event API.

diff --git a/configure.in b/configure.in
index 7ad8c04..f309755 100644
--- a/configure.in
+++ b/configure.in
@@ -793,6 +793,7 @@
 	libutil.h \
 	link.h \
 	linux/cdrom.h \
+	linux/input.h \
 	linux/joystick.h \
 	linux/ucdrom.h \
 	net/if.h \