Input: exc3000 - properly stop timer on shutdown

Input: exc3000 - properly stop timer on shutdown

[ Upstream commit 79c81d137d36f9635bbcbc3916c0cccb418a61dd ]

We need to stop the timer on driver unbind or probe failures, otherwise
we get UAF/Oops.

Fixes: 7e577a17f2ee ("Input: add I2C attached EETI EXC3000 multi touch driver")
Reported-by: "Stahl, Michael" <mstahl@moba.de>
Link: https://lore.kernel.org/r/Y9dK57BFqtlf8NmN@google.com
Cc: stable@vger.kernel.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>