change(micropython): Use CSPRNG to seed MP RNG

Closes #36

pycardium/mpconfigport.h

@@ -31,7 +31,7 @@
 #define MICROPY_MODULE_WEAK_LINKS           (1)
 
 /* urandom init */
-int mp_hal_trng_read_int(void);
+int mp_hal_csprng_read_int(void);
 
 /* Builtin function and modules */
 #define MICROPY_PY_ALL_SPECIAL_METHODS      (1)
@@ -43,7 +43,7 @@ int mp_hal_trng_read_int(void);
 #define MICROPY_PY_UJSON                    (1)
 #define MICROPY_PY_URANDOM                  (1)
 #define MICROPY_PY_URANDOM_EXTRA_FUNCS      (1)
-#define MICROPY_PY_URANDOM_SEED_INIT_FUNC   (mp_hal_trng_read_int())
+#define MICROPY_PY_URANDOM_SEED_INIT_FUNC   (mp_hal_csprng_read_int())
 #define MICROPY_PY_URE                      (1)
 #define MICROPY_PY_URE_MATCH_GROUPS         (1)
 #define MICROPY_PY_URE_MATCH_SPAN_START_END (1)

pycardium/mphalport.c

@@ -294,12 +294,12 @@ void NORETURN nlr_jump_fail(void *val)
 }
 
 /******************************************************************************
- * TRNG
+ * CSPRNG
  */
 
-int mp_hal_trng_read_int(void)
+int mp_hal_csprng_read_int(void)
 {
 	int result;
-	epic_trng_read((uint8_t *)&result, sizeof(result));
+	epic_csprng_read((uint8_t *)&result, sizeof(result));
 	return result;
 }