[libFuzzer] Migrate to the new exception syscalls on Fuchsia

This is part of the transition to the new Fuchsia exception syscalls
signature.

Differential Revision: https://reviews.llvm.org/D63897

llvm-svn: 364594
GitOrigin-RevId: d9a59aeb049ed070e665a29b16e697f20741c958
1 file changed