[yaml2obj][ELF] Add support for symbol indexes greater than SHN_LORESERVE

Right now Symbols must be either undefined or defined in a specific
section. Some symbols have section indexes like SHN_ABS however. This
change adds support for outputting symbols that have such section
indexes.

Patch by Jake Ehrlich

Differential Revision: https://reviews.llvm.org/D37391

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@312745 91177308-0d34-0410-b5e6-96231b3b80d8
5 files changed