HID: amd_sfh: Use correct MMIO register for DMA address

amd_stop_sensor_v2 accidentally used a different MMIO register than
amd_start_sensor_v2 for the DMA address.

Fixes: f264481a

 ("HID: amd_sfh: Extend driver capabilities for multi-generation support")
Signed-off-by: Dylan MacKenzie <ecstaticmorse@gmail.com>
Acked-by: Basavaraj Natikar <Basavaraj.Natikar@amd.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>