aya: fix bug with nested call relocations

Use the correct offset when looking up relocation entries while doing
nested call relocations.

aya/src/obj/relocation.rs

@@ -256,7 +256,8 @@ impl<'a> FunctionLinker<'a> {
                 continue;
             }
 
-            let callee_address = if let Some(rel) = rel_info((ins_index * INS_SIZE) as u64) {
+            let callee_address =
+                if let Some(rel) = rel_info(((ins_index - start_ins) * INS_SIZE) as u64) {
                     // We have a relocation entry for the instruction at `ins_index`, the address of
                     // the callee is the address of the relocation's target symbol.
                     rel_target_address(rel, self.symbol_table)?