[arm] implement addressing_mode_2 for loads/stores
[arm] implement addressing_mode_2 for loads/stores

cornell-brg/pydgin,futurecore/pydgin,futurecore/pydgin,moreati/pydgin,cornell-brg/pydgin,futurecore/pydgin,cornell-brg/pydgin,cornell-brg/pydgin,futurecore/pydgin,moreati/pydgin,moreati/pydgin,moreati/pydgin