Revert "rndis_host: Flag RNDIS modems as WWAN devices"

Revert "rndis_host: Flag RNDIS modems as WWAN devices"

This reverts commit 67d1a8956d2d62fe6b4c13ebabb57806098511d8. Since this
commit has been proven to be problematic for the setup of USB-tethered
ethernet connections and the related breakage is very noticeable for
users it should be reverted until a fixed version of the change can be
rolled out.

Closes: https://lore.kernel.org/all/e0df2d85-1296-4317-b717-bd757e3ab928@heusel.eu/
Link: https://chaos.social/@gromit/114377862699921553
Link: https://bugzilla.kernel.org/show_bug.cgi?id=220002
Link: https://bugs.gentoo.org/953555
Link: https://bbs.archlinux.org/viewtopic.php?id=304892
Cc: stable@vger.kernel.org
Acked-by: Lubomir Rintel <lkundrak@v3.sk>
Signed-off-by: Christian Heusel <christian@heusel.eu>
Link: https://patch.msgid.link/20250424-usb-tethering-fix-v1-1-b65cf97c740e@heusel.eu
Signed-off-by: Jakub Kicinski <kuba@kernel.org>