HID: sensor-hub: correct dyn_callback_lock IRQ-safe change

Commit 0ccf091d ("HID: sensor-hub:
make dyn_callback_lock IRQ-safe) was supposed to change locks
in sensor_hub_get_callback(), but missed.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>