Adding functions for calling random in core0.

Signed-off-by: Pol Henarejos <pol.henarejos@cttc.es>

src/rng/hwrng.h

@@ -20,10 +20,14 @@
 
 #define NEUG_PRE_LOOP 32
 
+#include <stdlib.h>
+#include "pico/stdlib.h"
+
 void neug_init(uint32_t *buf, uint8_t size);
 uint32_t neug_get();
 void neug_flush(void);
 void neug_wait_full(void);
+void neug_wait_full_ext(bool);
 void neug_fini(void);
 
 #endif