Prune RelocVisitor.h include to avoid including COFF.h from MCJIT.h

This helps to mitigate the conflict between COFF.h and winnt.h, which is
PR28399.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@274637 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/DebugInfo/DIContext.h

@@ -17,7 +17,6 @@
 
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/Object/ObjectFile.h"
-#include "llvm/Object/RelocVisitor.h"
 #include "llvm/Support/Casting.h"
 #include "llvm/Support/DataTypes.h"
 #include <string>

lib/DebugInfo/DWARF/DWARFContext.cpp

@@ -13,6 +13,8 @@
 #include "llvm/DebugInfo/DWARF/DWARFAcceleratorTable.h"
 #include "llvm/DebugInfo/DWARF/DWARFDebugArangeSet.h"
 #include "llvm/DebugInfo/DWARF/DWARFUnitIndex.h"
+#include "llvm/Object/MachO.h"
+#include "llvm/Object/RelocVisitor.h"
 #include "llvm/Support/Compression.h"
 #include "llvm/Support/Dwarf.h"
 #include "llvm/Support/ELF.h"

lib/DebugInfo/Symbolize/SymbolizableObjectFile.cpp

@@ -12,6 +12,7 @@
 //===----------------------------------------------------------------------===//
 
 #include "SymbolizableObjectFile.h"
+#include "llvm/Object/COFF.h"
 #include "llvm/Object/SymbolSize.h"
 #include "llvm/Support/DataExtractor.h"
 #include "llvm/DebugInfo/DWARF/DWARFContext.h"

lib/DebugInfo/Symbolize/Symbolize.cpp

@@ -20,6 +20,7 @@
 #include "llvm/DebugInfo/DWARF/DWARFContext.h"
 #include "llvm/DebugInfo/PDB/PDB.h"
 #include "llvm/DebugInfo/PDB/PDBContext.h"
+#include "llvm/Object/COFF.h"
 #include "llvm/Object/ELFObjectFile.h"
 #include "llvm/Object/MachO.h"
 #include "llvm/Object/MachOUniversal.h"

lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.h

@@ -20,6 +20,9 @@
 using namespace llvm;
 
 namespace llvm {
+namespace object {
+class ELFObjectFileBase;
+}
 
 class RuntimeDyldELF : public RuntimeDyldImpl {