[patch] Run tests in gdb.reverse

[Joel Brobecker]

> This patch is to convert variable checking in each reverse test case to
> a proc return value checking, so that gdb.reverse tests will be run on
> targets that support reverse debugging.

I haven't looked at the patch too closely, but I think that this is
a good idea. The part that I am worried about is perhaps the fact
that there might have been a reason for providing a manual control
for running these testcases. If that's the case, then we'll probably
want to add a control for forcing these testcase to be disabled.

-- 
Joel