fix build for several projects

see [my comment](https://github.com/libretro/libretro-super/commit/64b9c352ca4a610980f31cf83440d37bb5519bae#diff-902d91e70320e6869ebd2d2f56ffb13dR116)
Merge pull request #90 from l3iggs/patch-2

fix build for several projects