add a light mode feature to be agnostic of syscall #'s

The goal is to operate on new Windows versions that have different syscalls but DR still works (after https://github.com/DynamoRIO/dynamorio/issues/1598). We would add a feature that turns off syscall parameter checking and tries to only care about the bare minimum syscalls needed to track memory allocation: and since those are all in ntoskrnl and are exported, we should be able to read them dynamically from the wrappers (modulo hooks).

Xref #1848, #1826.