VMCI: Fix "always true condition"

vmci_send_datagram() returns an int, with negative values indicating failure.
But we store it locally in a u32, which makes comparison of >= 0 useless.
Fixed to use an int.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Andy King <acking@vmware.com>
Signed-off-by: Dmitry Torokhov <dtor@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/misc/vmw_vmci/vmci_guest.c

@@ -78,7 +78,7 @@ bool vmci_guest_code_active(void)
 u32 vmci_get_vm_context_id(void)
 {
 	if (vm_context_id == VMCI_INVALID_ID) {
-		u32 result;
+		int result;
 		struct vmci_datagram get_cid_msg;
 		get_cid_msg.dst =
 		    vmci_make_handle(VMCI_HYPERVISOR_CONTEXT_ID,