Build fixes for OS X
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cobex22
MegaMario 1.7 builds and runs fine on OS X using the attached patch.
Things might need to be tweaked to not affect other platforms. For example, I didn't know how to conditionalize the extra LDFLAGS needed to find system libraries on OS X. I also moved the log.txt file location to /tmp, but that'll probably need to be fixed for non-unix like systems such as Windows.
OS X build fixes
Not a bad patch. It overlaps a bit with mine, but perhaps it would be better to use pkg-config rather than hardcoding in Mac libraries.