534584945c
With this patch, the IPC service is changed to use the new RMIB facility to register and handle the "kern.ipc" sysctl subtree itself. The subtree was previously handled by the MIB service directly. This change improves locality of handling: especially the kern.ipc.sysvipc_info node has some peculiarities specific to the IPC service and is therefore better handled there. Also, since the IPC service is essentially optional to the system, this rearrangement yields a cleaner situation when the IPC service is not running: in that case, the MIB service will expose a few basic kern.ipc nodes indicating that no SysV IPC facilities are present. Those nodes will be overridden through RMIB when the IPC service is running. It should be easier to add the remaining (from NetBSD) kern.ipc nodes as well now. Test88 is extended with a new subtest that verifies that sysctl-based information retrieval for semaphore sets works as expected. Change-Id: I6b7730e85305b64cfd8418c0cc56bde64b22c584