DiskCache: allow relocations within the same ELF image

We would check the FileID of mapped sections, but BSS is an anonymous mapping.
Grab the ELF image extents when we parse the file, and add an additional check
to the relocation filter to bail out additional relocs if we know that size.

FEXCore/Source/Interface/Core/DiskCache.cpp

@@ -825,6 +825,11 @@ namespace DiskCache {
         if (Target >= Region->BeginVA && Target < Region->EndVA) {
           continue;
         }
+        // let it through if it's inside the same ELF image? (like bss)
+        if (Region->FileInfo.MappedSize && Target >= Region->FileStartVA && Target < Region->FileStartVA + Region->FileInfo.MappedSize) {
+          continue;
+        }
+
         auto TargetSection = CTX->SyscallHandler->LookupExecutableFileSection(Thread, Target);
         if (!TargetSection || TargetSection->FileInfo.FileId != Region->FileInfo.FileId) {
           // we don't know where it's pointing, so we don't know how to encode the offset, so we can't cache atm