udevd: fix REMOVE handling This reverts b67f944. Lazy loading of device properties does not work for devices that are received over netlink, as these are sealed. Reinstate the unconditional loading of the device db. Reported by: Mantas Mikulėnas <grawity@gmail.com>.

libsystemd: add sd-device library This provides equivalent functionality to libudev-device, but in the systemd style. The public API only caters to creating sd_device objects from for devices that already exist in /sys, there is no support for listening for monitoring events or creating devices received over the udev netlink protocol. The private API contains the necessary functionality to make sd-device a drop-in replacement for libudev-device, but which we would not otherwise want to export.