thermal: intel: int340x: Read DDR data rate for Nova Lake

Add support for reading DDR data rate from PCI config offset.

The register details are:

 CFG Offset : 0xE0
 Bits	   : 11:2

DDR Data rate is in 33.33 MTPS units.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
[ rjw: Rearrange code to avoid using goto and make declarations consistent ]
Link: https://patch.msgid.link/20260223190420.874853-1-srinivas.pandruvada@linux.intel.com
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>