Fix "bad wxCheckListBox index" warning when trying to create AR Code

Fixes issue
[7060](https://code.google.com/p/dolphin-emu/issues/detail?id=7060)
Don't spam PanicAlerts on wii save exports.
Merge pull request #742 from RachelBryk/stop-panicking

Don't spam PanicAlerts on wii save exports.
Update ISOProperties.cpp
Merge pull request #743 from RolandMunsil/fix-ar-code-warning

Fix "bad wxCheckListBox index" warning when trying to create AR Code
Core: Remove unused file DSPJitUtil.h
Merge pull request #744 from lioncash/unused-file

Core: Remove unused file DSPJitUtil.h