Fixed immediate mode for 20 bit instructions
Fixed immediate mode for 20 bit instructions

nfi/mspsim,cmorty/mspsim,contiki-os/mspsim,cmorty/mspsim,contiki-os/mspsim,joakimeriksson/mspsim,mspsim/mspsim,fvdnabee/mspsim,fvdnabee/mspsim,ransford/mspsim,joakimeriksson/mspsim,nfi/mspsim,ransford/mspsim,mspsim/mspsim