scudo: Don't define mallinfo2 on Android.

On Android, mallinfo2 is an alias of mallinfo, which results
in errors if we try to define both.

Differential Revision: https://reviews.llvm.org/D146324

GitOrigin-RevId: 9f42b04128bc5d3b9c8701ab83f8f7ba4e9b93b2
Change-Id: I2cb518227a5fe295ee88e31183d924ef7e67c914
1 file changed