Input: ili210x - use kvmalloc() to allocate buffer for firmware update

Input: ili210x - use kvmalloc() to allocate buffer for firmware update

Allocating a contiguous buffer of 64K may fail if memory is sufficiently
fragmented, and may cause OOM kill of an unrelated process. However we
do not need to have contiguous memory. We also do not need to zero
out the buffer since it will be overwritten with firmware data.

Switch to using kvmalloc() instead of kzalloc().

Link: https://lore.kernel.org/r/20240609234757.610273-1-dmitry.torokhov@gmail.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>