Improve support for arm-wince-pe target

[Richard Earnshaw]

>   @end html
> ! @heading @anchor{arm-*-elf}arm-*-elf
>   @heading @anchor{xscale-*-*}xscale-*-*
>   Advanced RISC Machines ARM-family processors.  Subtargets that use the
> ! ELF object format require GNU binutils 2.13 or newer.  Such subtargets
> ! include: @code{arm-*-freebsd}, @code{arm-*-netbsdelf},
> ! @code{arm-*-*linux}, @code{arm-*-rtems} and @code{arm-*-kaos}.
> ! 

We stopped using "Advanced RISC Machines" 5 years ago.  It's just "ARM 
Ltd" these days.

R.