Get HZ value from system rather than requiring via CPPFLAGS
Patch by Robin Getz <rgetz@blackfin.uclinux.org>
--- a/dhry.h
+++ b/dhry.h
@@ -359,6 +359,10 @@
/* for "times" */
#endif
+#ifndef HZ
+#include <sys/param.h>
+#endif
+
#define Mic_secs_Per_Second 1000000.0
/* Berkeley UNIX C returns process times in seconds/HZ */