Change Razer Abyssus DPI in 70-mouse.hwdb (#12029)

Change Razer Abyssus DPI in 70-mouse.hwdb (#12029)

As discussed in https://gitlab.freedesktop.org/libinput/libinput/issues/198#note_100642 the DPI for the Razer Abyssus mouse is not 3500 by default, but around 1600-1700 when measured with the mouse-dpi-tool.

So I have done some measurements now and always got a value of about 21000 device units on a distance of 12.5 inch. This would result in a calculated resolution of about 1680 DPI. Since such an odd number does not occur in the hwdb file I decided to round to 1600 DPI.