hwdb: add more mouse DPI entries
Plus a note for Logitech devices using the unified receiver: these devices
include their wireless PID in the name, the usb PID/VID is the same for all.
In kernel 3.19 the actual model number will be the name, but the patches are
still a bit in flux at this point. In the future each device will need two
entries for pre+3.19 and 3.19.
https://bugs.freedesktop.org/show_bug.cgi?id=87037
https://bugs.freedesktop.org/show_bug.cgi?id=87072
https://bugs.freedesktop.org/show_bug.cgi?id=87162