[patch/doc] Tweak "info inferiors" output.

[Eli Zaretskii]

> From: Pedro Alves <pedro@codesourcery.com>
> Date: Fri, 14 Aug 2009 16:46:00 +0100
> 
> Eli, documentation bits ok?

I have two comments:

  . Does "ID" and the numbers below it really fail to align, as the
    example shows?  If so, perhaps we should align them.

  . I'd prefer to explain what can appear under "Target".

Thanks.