This backs C++17's std::pmr implementation.

Wine-Bug: https://bugs.winehq.org/show_bug.cgi?id=49954Signed-off-by: Arkadiusz Hiler <ahiler@codeweavers.com>
Signed-off-by: Piotr Caban <piotr@codeweavers.com>
Signed-off-by: Alexandre Julliard <julliard@winehq.org>