various openbsd and general warning fixes - patch by Björn Sandell <biorn@dce.chalmers.se>

git-svn-id: file:///var/local/repositories/mplayer/trunk/postproc@6058 b3059339-0415-0410-9bf9-f77b7e298cf2

swscale.c

@@ -55,6 +55,8 @@ untested special converters
 #include <assert.h>
 #ifdef HAVE_MALLOC_H
 #include <malloc.h>
+#else
+#include <stdlib.h>
 #endif
 #include "swscale.h"
 #include "../cpudetect.h"