Re: (ITS#6177) bdb delete locking issue

[richton@nbcs.rutgers.edu]

Howard has me experimenting with moving the lock from cache.c to delete.c. 
With this experiment in place, I'm getting a failure with 
test008/back-bdb. Under libumem, the crash is in bdb_search line 752.

I see that rs->sr_un.sru_search.r_entry = 0xbaddcafebaddcafe -- 
uninitialized per libumem -- is being used as an argument to 
is_entry_subentry().

Backtrace:

https://www.nbcs.rutgers.edu/~richton/test008-bt-200906181020.txt

-d -1:

https://www.nbcs.rutgers.edu/~richton/test008-slapdlog-200906181020.txt