tipc: limit error messages relating to memory leak to one line

With the default name table size of 1024, it is possible that
the sanity check in tipc_nametbl_stop could spam out 1024
essentially identical error messages if memory was corrupted
or similar.  Limit it to issuing no more than a single message.

The actual chain number (i.e. 0 --> 1023) wouldn't provide any
useful insight if/when such an instance happened, so don't
bother printing out that value.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>