Set and get DPM policy for GPU device

Add new APIs to set and get dpm policy for the GPU device.

Change-Id: I26fa49cd17d0ce66bda3446c38945a6cf35717ff

example/amd_smi_nodrm_example.cc

@@ -331,6 +331,18 @@ int main() {
             printf("    Output of amdsmi_get_power_cap_info:\n");
             std::cout << "\t\t Power Cap: " << cap_info.power_cap / 1000000
                       << "W\n\n";
+
+            amdsmi_dpm_policy_t policy;
+            ret = amdsmi_get_dpm_policy(processor_handles[j], &policy);
+            if (ret != AMDSMI_STATUS_NOT_SUPPORTED) {
+                CHK_AMDSMI_RET(ret)
+                std::cout << "\t amdsmi_get_dpm_policy total:" << policy.num_supported
+                        <<" current:" << policy.current << "\n";
+                for (int x=0; x < policy.num_supported; x++) {
+                    std::cout << x <<": (" << policy.policies[x].policy_id
+                    <<"," << policy.policies[x].policy_description << ")\n";
+                }
+            }
         }
     }