platform/x86: intel-vbtn: Allow switch events on Acer Switch Alpha 12

platform/x86: intel-vbtn: Allow switch events on Acer Switch Alpha 12

This 2-in-1 model (Product name: Switch SA5-271) features a SW_TABLET_MODE
that works as it would be expected, both when detaching the keyboard and
when folding it behind the tablet body.

It used to work until the introduction of the allow list at
commit 8169bd3e6e193 ("platform/x86: intel-vbtn: Switch to an allow-list
for SW_TABLET_MODE reporting"). Add this model to it, so that the Virtual
Buttons device announces the EV_SW features again.

Fixes: 8169bd3e6e193 ("platform/x86: intel-vbtn: Switch to an allow-list for SW_TABLET_MODE reporting")
Cc: stable@vger.kernel.org
Signed-off-by: Carlos Garnacho <carlosg@gnome.org>
Link: https://lore.kernel.org/r/20201201135727.212917-1-carlosg@gnome.org
Signed-off-by: Hans de Goede <hdegoede@redhat.com>