[GWP-ASan] Maybe initialise GWP-ASan from Zygote.

Calls the GWP-ASan mallopt() to possibly install GWP-ASan for the zygote
child.

Bug: 135634846
Test: ??
Change-Id: I08d6797fa9b5ca10b97e0ab1efc2dc1c219c1b45
1 file changed