C++: Accept new dataflow IR inconsistencies

These are due to additional loads being generated on fields, and should not
cause any problems. Ideally, we should tune the definition of
`TPostFieldUpdateNode` to make these go away.

Author: jketema

cpp/ql/test/library-tests/dataflow/dataflow-tests/dataflow-ir-consistency.expected

@@ -14,6 +14,9 @@ localCallNodes
 postIsNotPre
 postHasUniquePre
 uniquePostUpdate
+| example.c:24:2:24:7 | coords indirection | Node has multiple PostUpdateNodes. |
+| example.c:24:13:24:18 | coords indirection | Node has multiple PostUpdateNodes. |
+| example.c:26:2:26:7 | coords indirection | Node has multiple PostUpdateNodes. |
 postIsInSameCallable
 reverseRead
 argHasPostUpdate

cpp/ql/test/library-tests/syntax-zoo/dataflow-ir-consistency.expected

@@ -15,6 +15,7 @@ localCallNodes
 postIsNotPre
 postHasUniquePre
 uniquePostUpdate
+| allocators.cpp:4:24:4:26 | this indirection | Node has multiple PostUpdateNodes. |
 | cpp11.cpp:82:17:82:17 | this indirection | Node has multiple PostUpdateNodes. |
 | cpp11.cpp:82:17:82:55 | [...](...){...} indirection | Node has multiple PostUpdateNodes. |
 | ir.cpp:514:10:514:11 | definition of r2 indirection | Node has multiple PostUpdateNodes. |
@@ -31,6 +32,8 @@ uniquePostUpdate
 | ir.cpp:777:3:777:11 | this indirection | Node has multiple PostUpdateNodes. |
 | ir.cpp:786:3:786:11 | this indirection | Node has multiple PostUpdateNodes. |
 | ir.cpp:795:3:795:11 | this indirection | Node has multiple PostUpdateNodes. |
+| misc.c:130:5:130:5 | s indirection | Node has multiple PostUpdateNodes. |
+| misc.c:131:5:131:6 | sp indirection | Node has multiple PostUpdateNodes. |
 | static_init_templates.cpp:240:7:240:7 | this indirection | Node has multiple PostUpdateNodes. |
 postIsInSameCallable
 reverseRead