HID: amd_sfh: Add a new interface for exporting HPD data

AMDSFH has information about the User presence information via the Human
Presence Detection (HPD) sensor which is part of the AMD sensor fusion hub.

Add a new interface to export this information, where other drivers like
PMF can use this information to enhance user experiences.

Link: https://lore.kernel.org/all/ad064333-48a4-4cfa-9428-69e8a7c44667@redhat.com/


Co-developed-by: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
Signed-off-by: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
Signed-off-by: Basavaraj Natikar <Basavaraj.Natikar@amd.com>
Signed-off-by: Jiri Kosina <jkosina@suse.com>