libudev: Move -lrt to Libs.private

It's only needed for static linking.

https://bugs.freedesktop.org/show_bug.cgi?id=63309
keymap: Add HP EliteBook 8460p

Taken from
https://code.launchpad.net/~pali/ubuntu/raring/udev/hp-elitebook-8460p/+merge/157420

Signed-off-by: Martin Pitt <martinpitt@gnome.org>
keymap: Fix typo in previous commit