Split random number functions off io.c, so that they can be documented

separately.

sysdep/unix/io.c

@@ -28,20 +28,6 @@
 #include "lib/unix.h"
 #include "lib/sysio.h"
 
-/*
- *	Random Numbers
- */
-
-u32
-random_u32(void)
-{
-  long int rand_low, rand_high;
-
-  rand_low = random();
-  rand_high = random();
-  return (rand_low & 0xffff) | ((rand_high & 0xffff) << 16);
-}
-
 /*
  *	Tracked Files
  */