qemu_domain.h: add G_DEFINE_AUTOPTR_CLEANUP_FUNC for qemuDomainLogContext

This will allow us to g_autoptr qemuDomainLogContext pointers
in the following patch.
Reviewed-by: NCole Robinson <crobinso@redhat.com>
Signed-off-by: NDaniel Henrique Barboza <danielhb413@gmail.com>

src/qemu/qemu_domain.h

@@ -586,6 +586,7 @@ void qemuProcessEventFree(struct qemuProcessEvent *event);
 
 typedef struct _qemuDomainLogContext qemuDomainLogContext;
 typedef qemuDomainLogContext *qemuDomainLogContextPtr;
+G_DEFINE_AUTOPTR_CLEANUP_FUNC(qemuDomainLogContext, virObjectUnref);
 
 typedef struct _qemuDomainSaveCookie qemuDomainSaveCookie;
 typedef qemuDomainSaveCookie *qemuDomainSaveCookiePtr;