iio: light: as73211: Ensure buffer holes are zeroed

iio: light: as73211: Ensure buffer holes are zeroed

commit 433b99e922943efdfd62b9a8e3ad1604838181f2 upstream.

Given that the buffer is copied to a kfifo that ultimately user space
can read, ensure we zero it.

Fixes: 403e5586b52e ("iio: light: as73211: New driver")
Reviewed-by: Matti Vaittinen <mazziesaccount@gmail.com>
Reviewed-by: Andy Shevchenko <andy@kernel.org>
Link: https://patch.msgid.link/20250802164436.515988-2-jic23@kernel.org
Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>