platin: added --ait-disable-builtin-sc workaround

To disable aiT's builtin stack cache analysis, we disable spilling/filling (by
setting the stack cache size to 0 for aiT) and  reserve the highest 32K in the
address space and direct all SC accesses there without causing any latency.
singlepath: various fixes
fix mistakenly introduced typo
WIP: realin stack option??
WIP: baseline opt experiment