Fix hardcoded section references in memory model appendix

src/mm-formal.adoc

@@ -8,11 +8,10 @@ discrepancies are unintended; the expectation is that the models
 describe exactly the same sets of legal behaviors.
 
 This appendix should be treated as commentary; all normative material is
-provided in <<memorymodel, Chapter 17>> and in the rest of
-the main body of the ISA specification. All currently known
-discrepancies are listed in
-<<discrepancies, Section A.7>>. Any other
-discrepancies are unintentional.
+provided in <<memorymodel>> and in the rest of
+the main body of the ISA specification.
+All currently known discrepancies are listed in <<discrepancies>>.
+Any other discrepancies are unintentional.
 
 [[alloy]]
 === Formal Axiomatic Specification in Alloy