kdc krb5_db_entry passed by value patch

[Chris Hecker]

So, as I mentioned, I'm finally porting all my old minor KDC fixes and 
features to the latest krb5 code.  Most of these are really small, but 
there's one that's a little larger, and it's fixing the krb5_db_entry 
being passed by value in a bunch of places.  I fixed this locally years 
ago so I could make some of my other changes easier, and I just 
discovered this is actually listed in 
https://k5wiki.kerberos.org/wiki/Cleanups "Some kdc_util.c functions 
take krb5_db_entry structures instead of pointers."

I would like to contribute a patch for this, but if it is unlikely to be 
accepted (it's a simple code fix but it touches a fair number of lines, 
my patch for 1.9 is 364 lines long, I assume the update would be about 
the same), then I will actually not do the patch locally and I'll fix my 
other patches to use the passed-by-value db entries in order to make my 
life simpler when merging from the official code as it evolves.  
Hopefully that makes sense.

Hopefully you guys want this patch and I can just port it to the master 
branch and make a pull request, but if not, please let me know so I 
don't waste a bunch of work.

Thanks,
Chris