Update nterp to advance PC early on branches

Nterp checks if a suspension is required on backward branches. The
PC update was happening after the suspend point. So it appeared as
if we are suspending at the branch instead of at the loop header.
This isn't a correctness issue but updating PC early makes it consistent
with interpreter and JITed code.

Bug: 206029744
Change-Id: Id66706aea59a616220ff254d37aafbeeb188ffed
4 files changed