Change clock back to 250 MHz

Signed-off-by: Jan Hamal Dvořák <mordae@anilinux.org>

src/main.c

@@ -34,7 +34,7 @@
 #include <limits.h>
 #include <stdlib.h>
 
-#define CLK_SYS_HZ (264 * MHZ)
+#define CLK_SYS_HZ (250 * MHZ)
 
 #define EXTRA_BITS 4
 #define NUM_SAMPLES 32