[MPlayer-dev-eng] removing USE_MACSHLB from vd_realvid ad_realaud

[Nicolas Plourde]

I think this should be removed from mplayer. It is only use in 
vd_realvid/ad_realaud codec and the codec package
of real shlib do not work anyway. I sugest going back to the HAVE_LIBDL 
path and use helix codec
library that work properly.

If someone oppose to this let me know. I will submit a patch soon.
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Nicolas Plourde <nicolas.plourde at sympatico.ca>