[commit] Deprecate add_set_cmd

[Eli Zaretskii]

> Date: Mon, 21 Feb 2005 12:17:13 -0500
> From: Andrew Cagney <cagney@gnu.org>
> 
> (gdb) maintenance show-debug-registers <boolean>
> 
> do not.  They should be replaced with something like:
> 
> (gdb) set|show maintenance show-debug-registers
> or
> (gdb) maintenance set|show show-debug-registers

I'd prefer the latter.