Move UnwindTable from ObjectFile to Module

Summary:
This is a preparatory step to enable adding extra unwind strategies by
symbol file plugins. This has been discussed on the lldb-dev mailing
list: <http://lists.llvm.org/pipermail/lldb-dev/2019-February/014703.html>.

Reviewers: jasonmolenda, clayborg, espindola

Subscribers: lemo, emaste, lldb-commits, arichardson

Differential Revision: https://reviews.llvm.org/D58129

llvm-svn: 354033

lldb/source/Plugins/ObjectFile/ELF/ObjectFileELF.cpp

@@ -2862,8 +2862,8 @@ Symtab *ObjectFileELF::GetSymtab() {
       }
     }
 
-    DWARFCallFrameInfo *eh_frame = GetUnwindTable().GetEHFrameInfo();
-    if (eh_frame) {
+    if (DWARFCallFrameInfo *eh_frame =
+            GetModule()->GetUnwindTable().GetEHFrameInfo()) {
       if (m_symtab_up == nullptr)
         m_symtab_up.reset(new Symtab(this));
       ParseUnwindSymbols(m_symtab_up.get(), eh_frame);