chore(circuits): rename function to validate private call hash in PKC (it pops too) (#1418)

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Author: dbanks12

circuits/cpp/src/aztec3/circuits/kernel/private/native_private_kernel_circuit_inner.cpp

@@ -74,13 +74,14 @@ namespace aztec3::circuits::kernel::private_kernel {
 //     return aggregation_object;
 // }
 
-void validate_this_private_call_hash(DummyCircuitBuilder& builder,
-                                     PrivateCallData<NT> const& private_call,
-                                     KernelCircuitPublicInputs<NT>& public_inputs)
+void pop_and_validate_this_private_call_hash(
+    DummyCircuitBuilder& builder,
+    PrivateCallData<NT> const& private_call,
+    std::array<NT::fr, MAX_PRIVATE_CALL_STACK_LENGTH_PER_TX>& private_call_stack)
 {
     // TODO(mike): this logic might need to change to accommodate the weird edge 3 initial txs (the 'main' tx, the 'fee'
     // tx, and the 'gas rebate' tx).
-    const auto popped_private_call_hash = array_pop(public_inputs.end.private_call_stack);
+    const auto popped_private_call_hash = array_pop(private_call_stack);
     const auto calculated_this_private_call_hash = private_call.call_stack_item.hash();
 
     builder.do_assert(
@@ -151,7 +152,7 @@ KernelCircuitPublicInputs<NT> native_private_kernel_circuit_inner(DummyCircuitBu
 
     validate_inputs(builder, private_inputs);
 
-    validate_this_private_call_hash(builder, private_inputs.private_call, public_inputs);
+    pop_and_validate_this_private_call_hash(builder, private_inputs.private_call, public_inputs.end.private_call_stack);
 
     common_validate_call_stack(builder, private_inputs.private_call);