HID: input: add mapping for "Toggle Display" key

[ Upstream commit c01908a14bf735b871170092807c618bb9dae654 ]

According to HUT 1.12 usage 0xb5 from the generic desktop page is reserved
for switching between external and internal display, so let's add the
mapping.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>