[MPlayer-dev-eng] Fix compilation where libm exports erf

[Etienne Buira]

Define HAVE_ERF in accordance with what is exported by libm.

Regards.

-------------- next part --------------
A non-text attachment was scrubbed...
Name: test_for_erf.patch
Type: text/x-diff
Size: 715 bytes
Desc: not available
URL: <http://lists.mplayerhq.hu/pipermail/mplayer-dev-eng/attachments/20151221/bd6b455b/attachment.patch>