powerpc/perf/hv-24x7: Add missing put_cpu_var()

Add missing put_cpu_var() for 24x7 requests. This went missing in
commit f34b6c72 (3.18-rc3).
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/perf/hv-24x7.c

@@ -1096,7 +1096,7 @@ static unsigned long single_24x7_request(struct perf_event *event, u64 *count)
 
 	ret = add_event_to_24x7_request(event, request_buffer);
 	if (ret)
-		return ret;
+		goto out;
 
 	ret = make_24x7_request(request_buffer, result_buffer);
 	if (ret) {
@@ -1109,6 +1109,8 @@ static unsigned long single_24x7_request(struct perf_event *event, u64 *count)
 	*count = be64_to_cpu(resb->elements[0].element_data[0]);
 
 out:
+	put_cpu_var(hv_24x7_reqb);
+	put_cpu_var(hv_24x7_resb);
 	return ret;
 }