Remove powerpc32 sqrt wrappers

[Gabriel F. T. Gomes]

On Thu, 24 Aug 2017 20:33:10 +0000
Joseph Myers <joseph@codesourcery.com> wrote:

>Note that benchtests of sqrt deliberately use -fno-builtin, specifically 
>because the point is to benchmark glibc's implementations rather than the 
>compiler's inline code.
>
>Thus those benchtests may indicate how much performance (if any) is gained 
>(given -fno-builtin) from the custom sqrt wrappers, compared with code 
>generated by a modern GCC version that can do shrink wrapping (the 
>comments in the powerpc32 wrappers say "Until gcc supports prologue 
>shrink-wrapping this is the best we can do.", i.e. they were intended to 
>improve on the performance of code built with old GCC).  But they are also 
>fairly peripheral to my main point (that in the normal case, without 
>-fno-builtin, these wrappers will only ever be called for 
>non-performance-relevant error cases, and not even those with 
>-fno-math-errno).

Fair enough.
The patch looks good to me.