kvm: do not flush after deleting gsi

Deleting a GSI isn't necessary: it is enough
to stop using it. Delay flush until an entry is used.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

kvm-all.c

@@ -991,8 +991,6 @@ void kvm_irqchip_release_virq(KVMState *s, int virq)
         }
     }
     clear_gsi(s, virq);
-
-    kvm_irqchip_commit_routes(s);
 }
 
 static unsigned int kvm_hash_msi(uint32_t data)