Remove PlainPointer, RelativePointer and RelativeFixupPointer (#57707)

- Removed all uses of PlainPointer
- Remove all use of RelativeFixupPointer
- Remove all use of FixupPointer
- Remove RelativePointer

- Debugging all of this is now easier! Yay!

Fixes #57706 

Co-authored-by: Jeremy Koritzinsky <[email protected]>

Author: davidwrighton

src/coreclr/debug/daccess/request.cpp

@@ -918,7 +918,7 @@ HRESULT ClrDataAccess::GetMethodDescData(
             methodDescData->bHasNativeCode = FALSE;
             methodDescData->NativeCodeAddr = (CLRDATA_ADDRESS)-1;
         }
-        methodDescData->AddressOfNativeCodeSlot = pMD->HasNativeCodeSlot() ? TO_CDADDR(pMD->GetAddrOfNativeCodeSlot()) : NULL;
+        methodDescData->AddressOfNativeCodeSlot = pMD->HasNativeCodeSlot() ? TO_CDADDR(dac_cast<TADDR>(pMD->GetAddrOfNativeCodeSlot())) : NULL;
         methodDescData->MDToken = pMD->GetMemberDef();
         methodDescData->MethodDescPtr = methodDesc;
         methodDescData->MethodTablePtr = HOST_CDADDR(pMD->GetMethodTable());

src/coreclr/inc/corcompile.h

@@ -26,7 +26,6 @@
 #include <daccess.h>
 #include <corbbtprof.h>
 #include <clrtypes.h>
-#include <fixuppointer.h>
 
 typedef DPTR(struct CORCOMPILE_EXCEPTION_LOOKUP_TABLE)
     PTR_CORCOMPILE_EXCEPTION_LOOKUP_TABLE;