[v3, 3.4 & HEAD] set cpu_include_dir for mips*-*-linux* and arm*-linux-* targets, update baseline file

[Paolo Carlini]

Matthias Klose wrote:

>Ok here is the updated patch, arm included as well. IIRC the baseline
>is the the same for mips64{,el} and mips{,el}, and we don't care about
>the emotion engine (please see mail exchange below). Ok to checkin?
>  
>
You already have my off-line pre-approval for the arm*-*-linux* change
(if the ARM maintainers and the other libstdc++-v3 maintainers do not 
object,
and conditional to testing, of course). However, you have not answered
yet my comment about mips*-*-linux*:

>+    cpu_include_dir="cpu/mips"
>  
>
Is this really necessary?

Paolo.