Make NaCl's use of .init_array for static constructors match Linux

Summary:
The generic ELF TargetObjectFile defaults to .ctors, but Linux's
defaults to .init_array by calling InitializeELF with the value of
UseInitArray from TargetMachine. Make NaCl's behavior match.

Reviewers: jvoung
Differential Revision: http://reviews.llvm.org/D8240

llvm-svn: 231934
4 files changed