Kobo driver: Fix latest firmware update for Kobo Wifi causing calibre to not recognize it. Fixes #1251536 [Calibre not recognizing Kobo device](https://bugs.launchpad.net/calibre/+bug/1251536)

Bug #1251536 reports an updated firmware for the Kobo WiFi. This also
changed the device id fromPID=0x4161 to PID=0x4162. It also needed an
update to the DBVersion.
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