RFR(S) 8173795: AOT support in raw_exception_handler_for_return_address is broken

[dean.long at oracle.com]

https://bugs.openjdk.java.net/browse/JDK-8173795

http://cr.openjdk.java.net/~dlong/8173795/hs.0

In raw_exception_handler_for_return_address(), AOT does not take 
advantage of the optimized unpack_with_exception deoptimization path.  
This fix removes special-purpose AOT code and instead enables both AOT 
and nmethod code to take the same path.

dl