thermal: tsens: Update sensor ID index

tsens_get_hw_id_mapping() API is used by thermal
client to obtain the logical ID or HW ID mapping
for the available temperature sensors (TSENS)
controller with sensor ID details. Clients
currently query the driver on a per sensor basis.
The API update allows the clients to get the sensor
ID information at once for the available number
of sensors.

Change-Id: I8f9aabe6eda58baa05bf079f04ef8167a5a05400
Signed-off-by: Rama Krishna Phani A <rphani@codeaurora.org>