D67284 introduced ARMErrataFix.cpp which was derived from AArch64ErrataFix.cpp. There were some useful refactoring changes made to ARMErrataFix.cpp made as part of the review. This change applies the relevant changes back to AArch64ErrataFix.cpp. Main changes are:
- Old style variable names in comments like IS, are now new style isec.
- Simplify init() collection of mappingSymbols to always start with a code mapping symbol.
- Simplify logic in mergeCmp().
- Fix one 80 column overflow caused by IS -> isec transformation.