HID: fix missing irq field

commit ba18a931 ("Revert "HID: i2c-hid: Add support for ACPI GPIO
interrupts"") removed the need for storing the irq in struct i2c_hid.

But then commit de3c99488609 ("HID: i2c-hid: Disable IRQ before freeing
buffers") forgot to update the location of the irq.

Fix this by using the actual I2C client irq.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>