Use more consistent names

Reviewing another change I noticed that we use "getSymbols" to mean
different things in different files. Depending on the file it can
return

ArrayRef<StringRef>
ArrayRef<SymbolBody*>
ArrayRef<Symbol*>
ArrayRef<Elf_Sym>

With this change it always returns an ArrayRef<SymbolBody*>. The other
functions are renamed getELFsyms() and getSymbolNames().

Note that we cannot return ArrayRef<Symbol*> instead of
ArreyRef<SymbolBody*> because local symbols have a SymbolBody but not
a Symbol.

llvm-svn: 309840
diff --git a/lld/ELF/LTO.cpp b/lld/ELF/LTO.cpp
index bf2dadc..3657f7c 100644
--- a/lld/ELF/LTO.cpp
+++ b/lld/ELF/LTO.cpp
@@ -127,15 +127,15 @@
 void BitcodeCompiler::add(BitcodeFile &F) {
   lto::InputFile &Obj = *F.Obj;
   unsigned SymNum = 0;
-  std::vector<Symbol *> Syms = F.getSymbols();
+  std::vector<SymbolBody *> Syms = F.getSymbols();
   std::vector<lto::SymbolResolution> Resols(Syms.size());
 
   // Provide a resolution to the LTO API for each symbol.
   for (const lto::InputFile::Symbol &ObjSym : Obj.symbols()) {
-    Symbol *Sym = Syms[SymNum];
+    SymbolBody *B = Syms[SymNum];
+    Symbol *Sym = B->symbol();
     lto::SymbolResolution &R = Resols[SymNum];
     ++SymNum;
-    SymbolBody *B = Sym->body();
 
     // Ideally we shouldn't check for SF_Undefined but currently IRObjectFile
     // reports two symbols for module ASM defined. Without this check, lld