Fixed Building the simulator with CAN_USE_UNALIGNED_ACCESSES defined.

Fixed a bug in the code generator where it was doing unaliged read and write.
Review URL: http://codereview.chromium.org/6598062

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@6983 ce2b1a6d-e550-0410-aec6-3dcde31c8c00