Wav file were not read correctly when encoutering most chunk type beside the ones used by QuakeForge.
This patch will fix the riff loader code so that unused but defined chunk are skipped. Most wav files should now be loaded correctly fixing some silent sound effect.
Also fixed a typo in wav loader and reordered wav validity check so that format is checked first. The data chunk could be inexistant on some weird format and so an invalid format is a more helpful error text.
! Fix: Skip unsupported chunk in riff loader instead of rejecting riff file.
! Fix: typo in Microsoft name.
! Fix: ordering of wav validity to enable more helpful error text.
