lib{atomic, itm}/configure.tgt uses -mcpu=v9 as default for sparc

[Eric Botcazou]

> # Map the target cpu to an ARCH sub-directory.  At the same time,
> # work out any special compilation flags as necessary.
> 
> case "${target_cpu}" in
> 
> ...
> 
>   sparc)
>         case " ${CC} ${CFLAGS} " in
>           *" -m64 "*)
>             ;;
>           *)
>             if test -z "$with_cpu"; then
>               XCFLAGS="${XCFLAGS} -mcpu=v9"
>             fi
>         esac
>         ARCH=sparc
>         ;;
> 
> --------
> 
> Prevents compilation of gcc-4.8.2 under NetBSD 6.4.1, throws Illegal
> Instruction during those lib{atomic, itm} final stage configure.
> 
> Removing "-mcpu=v9" allows the build to finalize.
> 
> System is a QEMUlated SparcStation 5. Not the best target for testing,
> but I understand this is a bug nonetheless.

IIRC both libraries require the V9 architecture to work properly/efficiently.

-- 
Eric Botcazou