utils/basic-decompiler/main.cpp: Added explicit
utils/basic-decompiler/main.cpp: This commit

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Intended original commit message: Added explicit (s32) casts for source registers of sign-dependent MIPS instructions. This should prevent sign-errors to occur in reverse engineered code using the output of the basic-decompiler as its base.
Merge pull request #41 from uofw/Basic-Decompiler-Updates

Basic decompiler: Added sign casts