commit ec7f68e0 upstream.

We can't store the trigger instance created by iio_trigger_alloc, in
trig field of iio_device structure. This needs to be stored in the
driver private data. Othewise it can result in crash during module
unload. Hence created a trig_ptr in the common data structure
for each HID sensor IIO driver and storing here.
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>