Add _end symbol for dynamic libraries. At least brk/sbrk in libc on
NetBSD need it.


git-svn-id: https://llvm.org/svn/llvm-project/lld/trunk@190752 91177308-0d34-0410-b5e6-96231b3b80d8
If .bss doesn't exist, set _end/end based on .data.


git-svn-id: https://llvm.org/svn/llvm-project/lld/trunk@190753 91177308-0d34-0410-b5e6-96231b3b80d8
Output soname.


git-svn-id: https://llvm.org/svn/llvm-project/lld/trunk@190758 91177308-0d34-0410-b5e6-96231b3b80d8
[PECOFF] Use a dummy file as an "input file" for Idata atoms.

git-svn-id: https://llvm.org/svn/llvm-project/lld/trunk@190772 91177308-0d34-0410-b5e6-96231b3b80d8