[opus] Check for alloca() in <malloc.h> as well as <alloca.h>

[Jonathan Lennox]

On the IRC channel, RiCON mentioned the patch https://github.com/Alexpux/MINGW-packages/blob/master/mingw-w64-opus/0001-correctly-detect-alloca.mingw.patch , which apparently is necessary on MinGW.

That patch had the disadvantage of breaking platforms that have <alloca.h> but not <malloc.h>.  The attached patch should handle either case.
-------------- next part --------------
A non-text attachment was scrubbed...
Name: 0001-Check-for-alloca-in-both-alloca.h-and-malloc.h.patch
Type: application/octet-stream
Size: 1520 bytes
Desc: 0001-Check-for-alloca-in-both-alloca.h-and-malloc.h.patch
URL: <http://lists.xiph.org/pipermail/opus/attachments/20160708/3781557e/attachment.obj>