Add Waltop Batteryless Tablet 172f:0505 aka Medion P82013 (MD 86457)

[Janfel]

• Waltop Batteryless Tablet (172f:0505)
• Sold as "USB-Grafiktablett MEDION P82013 (MD 86457)" by Medion
• Sysinfo: Waltop Batteryless Tablet (172f:0505) aka Medion P82013 (MD 86457) wacom-hid-descriptors#489
• User Manual (German): https://download2.medion.com/downloads/anleitungen/bda_md86457_de-an.pdf
• Physical working area is 8×5″, reported by libinput as 200×125mm
• Resolution is stated as 4000 LPI
• Pressure sensitivity range is 0-2047, but the reported values seem to grow exponentially rather than linearly (see https://gitlab.freedesktop.org/libinput/libinput/-/issues/1146#note_2974640).

The tablet also reports stylus tilt levels, which I wasn’t sure how to note in the .tablet file.

[whot]

The tablet also reports stylus tilt levels, which I wasn’t sure how to note in the .tablet file.

that's fine, no need for that because we get that information from the kernel (incorrectly in your case but well, you can't have everything ;). the libwacom .tablet file only needs to contain data we cannot get from the kernel.

This LGTM, thanks heaps