Fix math_private.h multiple include guards [committed]

[Joseph Myers]

On Sat, 21 Nov 2015, Andreas Schwab wrote:

> Joseph Myers <joseph@codesourcery.com> writes:
> 
> > 	* sysdeps/arm/math_private.h [!_MATH_PRIVATE_H]: Change guard to
> > 	[!ARM_MATH_PRIVATE_H].
> > 	[!ARM_MATH_PRIVATE_H] (ARM_MATH_PRIVATE_H): Define macro.
> 
> That should be _ARM_MATH_PRIVATE_H, etc.

This is an internal header, not an installed header, so I see no need for 
the leading underscore (and there is no consistency in that regard in 
headers unchanged by my patch, e.g. AARCH64_MATH_PRIVATE_H but 
_PPC_MATH_PRIVATE_H_).

-- 
Joseph S. Myers
joseph@codesourcery.com