APMF spec has a newer section called the APTS (AMD Performance and
Thermal State) information, where each slider/power mode is associated
with an index number.

Add support to get these indices for the Static Slider.
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Co-developed-by: Patil Rajesh Reddy <Patil.Reddy@amd.com>
Signed-off-by: Patil Rajesh Reddy <Patil.Reddy@amd.com>
Signed-off-by: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
Link: https://lore.kernel.org/r/20240306114415.3267603-6-Shyam-sundar.S-k@amd.comSigned-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>