vCPU hotunplug related leak reported by Valgrind:

==102631== 56 bytes in 1 blocks are definitely lost in loss record 5,089 of 8,555
==102631==    at 0x4C3ADBB: calloc (vg_replace_malloc.c:1117)
==102631==    by 0x69EE4CD: g_malloc0 (in /usr/lib64/libglib-2.0.so.0.5600.4)
==102631==    by 0x924452: kvm_start_vcpu_thread (kvm-accel-ops.c:69)
==102631==    by 0x4505C2: qemu_init_vcpu (cpus.c:643)
==102631==    by 0x76B4D1: x86_cpu_realizefn (cpu.c:6520)
==102631==    by 0x9344A7: device_set_realized (qdev.c:531)
==102631==    by 0x93E329: property_set_bool (object.c:2273)
==102631==    by 0x93C2F8: object_property_set (object.c:1408)
==102631==    by 0x940796: object_property_set_qobject (qom-qobject.c:28)
==102631==    by 0x93C663: object_property_set_bool (object.c:1477)
==102631==    by 0x933D3B: qdev_realize (qdev.c:333)
==102631==    by 0x455EC4: qdev_device_add_from_qdict (qdev-monitor.c:713)

Signed-off-by: Mark Kanda <mark.kanda@oracle.com>
---
 accel/accel-common.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/accel/accel-common.c b/accel/accel-common.c
index 80b0d909b2..ae71a27799 100644
--- a/accel/accel-common.c
+++ b/accel/accel-common.c
@@ -140,4 +140,5 @@ type_init(register_accel_types);
 void destroy_vcpu_thread_generic(CPUState *cpu)
 {
     g_free(cpu->thread);
+    g_free(cpu->halt_cond);
 }
-- 
2.27.0