enable sincos optimization on cygming targets

[Alexandre Oliva]

Err, sorry, I mislabeled this patch as [FYI,Ada], but it is neither
about Ada nor pre-approved.  It does require a review before I can check
it in.

On Oct 22, 2020, Alexandre Oliva <oliva@adacore.com> wrote:

> for  gcc/ChangeLog

> 	* config/i386/cygming.h (TARGET_LIBC_HAS_FUNCTION): Enable
> 	sincos optimization.

> -#define TARGET_LIBC_HAS_FUNCTION no_c99_libc_has_function
> +#define TARGET_LIBC_HAS_FUNCTION gnu_libc_has_function
 
-- 
Alexandre Oliva, happy hacker
https://FSFLA.org/blogs/lxo/
Free Software Activist
GNU Toolchain Engineer