Add an implementation for llvm-nm’s -print-file-name option (aka -o and -A).

The -print-file-name option in llvm-nm is to precede each symbol
with the object file it came from.  While code for the parsing of this
option and its aliases existed there was no code to implement it.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213906 91177308-0d34-0410-b5e6-96231b3b80d8