Add support to XGMI physical id

Get XGMI physical id from sysfs.

Change-Id: Ifd9e431bc2fbfd759d888a71b99046a5eb07b6ed

example/amd_smi_nodrm_example.cc

@@ -140,7 +140,9 @@ int main() {
             printf("\tDeviceID: 0x%lx\n", asic_info.device_id);
             printf("\tVendorID: 0x%x\n", asic_info.vendor_id);
             printf("\tRevisionID: 0x%x\n", asic_info.rev_id);
-            printf("\tAsic serial: 0x%s\n\n", asic_info.asic_serial);
+            printf("\tAsic serial: 0x%s\n", asic_info.asic_serial);
+            printf("\tXGMI physical id: 0x%x\n\n",
+                            asic_info.xgmi_physical_id);
 
             // Get VBIOS info
             amdsmi_vbios_info_t vbios_info = {};