remove libusb-legacy and point its users at libusb-compat

git-svn-id: svn://svn.openwrt.org/openwrt/packages@35388 3c298f89-4303-0410-b956-a3cf2f4a3e73
nut: fix remaining reference to libusb

git-svn-id: svn://svn.openwrt.org/openwrt/packages@35391 3c298f89-4303-0410-b956-a3cf2f4a3e73