Fix the compilation of dct-test, fft-test and motion-test which are using

random().

Originally committed as revision 9754 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/dct-test.c

@@ -42,6 +42,7 @@
 #endif
 
 #undef printf
+#undef random
 
 void *fast_memcpy(void *a, const void *b, size_t c){return memcpy(a,b,c);};
 

libavcodec/fft-test.c

@@ -31,6 +31,7 @@
 #include <string.h>
 
 #undef exit
+#undef random
 
 int mm_flags;
 

libavcodec/motion-test.c

@@ -35,6 +35,7 @@
 
 #undef exit
 #undef printf
+#undef random
 
 #define WIDTH 64
 #define HEIGHT 64