iio: light: hid-sensor-als.c: Fix memory leak in probe()

iio: light: hid-sensor-als.c: Fix memory leak in probe()

[ Upstream commit 9ecdbed7903921f29adae63a3155814b453e7186 ]

'channels' is allocated via kmemdup and it is never freed in the
subsequent error paths.

Use 'indio_dev->channels' directly instead, so that we avoid such
memory leak problem.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Reviewed-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>