[PATCH] Delegate PSTL configuration to pstl/pstl_config.h

[Thomas Rodgers]

Jonathan Wakely writes:

> On 18/04/19 17:02 -0700, Thomas Rodgers wrote:
>>
>>	 * include/bits/c++config: Remove explicit PSTL configuration
>>	 macros and use definitions from <pstl/pstl_config.h>.
>
> OK for trunk, thanks.

Tested x86_64-linux-gnu, committed to trunk.