Input: cyttsp5 - fix array length

Input: cyttsp5 - fix array length

commit 529de2f1ca3f0898c0d905b7d355a43dce1de7dc upstream.

The cmd array should be initialized with the proper command size and not
with the actual command value that is sent to the touchscreen.

Signed-off-by: Maximilian Weigand <mweigand@mweigand.net>
Reviewed-by: Alistair Francis <alistair@alistair23.me>
Link: https://lore.kernel.org/r/20230501113010.891786-2-mweigand@mweigand.net
Fixes: 5b0c03e24a06 ("Input: Add driver for Cypress Generation 5 touchscreen")
Cc: stable@vger.kernel.org
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>