[patch] Forbid run with a core file loaded

[Joel Brobecker]

> Joel, requesting approval for the 7.2 branch.
> There is also less intrusive patch
> 	http://cvs.fedoraproject.org/viewvc/rpms/gdb/F-13/gdb-bz594560-core-vs-process.patch?content-type=text%2Fplain&view=co
> which does not remove the process_stratum.

I am inclined hold off this patch off the branch (patch is too intrusive
this late in the game, problem is too minor [IMO]).  But Pedro has a better
understanding of the patch, and if he thinks it's safe to put in, then
that's good enough to go in 7.2.

-- 
Joel