staging/lustre/lnet: Get rid of IOC_LIBCFS_DEBUG_PEER hack

IOC_LIBCFS_DEBUG_PEER was added back in the stone ages to print debug
statistics on a peer when peer timeout happens.
Redo it properly as a separate LNet API call,
also get rid of "ioctl" forwarding into the underlying LNDs,
since no current LNDs implement this function anymore.

Signed-off-by: Oleg Drokin <green@linuxhacker.ru>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>