Remove duplicate symbols from libstdc++
Remove duplicate symbols from libstdc++

GCC's configure script hard-codes which math functions are available
from newlib. However, it misses a few, causing libstdc++ to provide an
implementation as well. This leads to duplicate symbols when both are
linked in.

Until/unless a fix is merged into GCC, we can correct their mistake by
modifying config.h after configuration.

PiperOrigin-RevId: 224191020

google/asylo,google/asylo,google/asylo,google/asylo,google/asylo,google/asylo