tools/power/x86/intel-speed-select: Add missing free cpuset

During perf level change cpuset is allocated but not freed.
Add free_cpu_set() in success and failure path.

Although this is not an issue, as the program will exit after
processing of online/offline, but for completeness add the
free_cpu_set().
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>

tools/power/x86/intel-speed-select/isst-config.c

@@ -1271,7 +1271,7 @@ static void set_tdp_level_for_cpu(struct isst_id *id, void *arg1, void *arg2, vo
 		ret = isst_get_coremask_info(id, tdp_level, &ctdp_level);
 		if (ret) {
 			isst_display_error_info_message(1, "Can't get coremask, online/offline option is ignored", 0, 0);
-			return;
+			goto free_mask;
 		}
 		if (ctdp_level.cpu_count) {
 			int i, max_cpus = get_topo_max_cpus();
@@ -1288,6 +1288,8 @@ static void set_tdp_level_for_cpu(struct isst_id *id, void *arg1, void *arg2, vo
 				}
 			}
 		}
+free_mask:
+		free_cpu_set(ctdp_level.core_cpumask);
 	}
 }