Input: usbtouchscreen - switch to using __free() cleanup facility

Use __free(kfree) cleanup facility when allocating temporary buffers
for USB transfers.

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20240712051851.3463657-8-dmitry.torokhov@gmail.com


Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>