[lld][ELF] process fini_array sections

This change processes fini_array section in addition to processing
init_array sections. This also makes functions registered at compile
time for initialization and finalization to be run during execution

git-svn-id: https://llvm.org/svn/llvm-project/lld/trunk@189196 91177308-0d34-0410-b5e6-96231b3b80d8
[lld][ELF][Cleanup] Create multiclass for variations in options usage

git-svn-id: https://llvm.org/svn/llvm-project/lld/trunk@189197 91177308-0d34-0410-b5e6-96231b3b80d8