make fortuna_update_seed() public

In order to be able to implement UpdateSeedFile from the original paper
this is required to be available on the public API.

src/headers/tomcrypt_prng.h

@@ -152,9 +152,10 @@ int fortuna_add_random_event(unsigned long source, unsigned long pool, const uns
 int fortuna_ready(prng_state *prng);
 unsigned long fortuna_read(unsigned char *out, unsigned long outlen, prng_state *prng);
 int fortuna_done(prng_state *prng);
-int  fortuna_export(unsigned char *out, unsigned long *outlen, prng_state *prng);
-int  fortuna_import(const unsigned char *in, unsigned long inlen, prng_state *prng);
-int  fortuna_test(void);
+int fortuna_export(unsigned char *out, unsigned long *outlen, prng_state *prng);
+int fortuna_import(const unsigned char *in, unsigned long inlen, prng_state *prng);
+int fortuna_update_seed(const unsigned char *in, unsigned long inlen, prng_state *prng);
+int fortuna_test(void);
 extern const struct ltc_prng_descriptor fortuna_desc;
 #endif
 

src/prngs/fortuna.c

@@ -167,7 +167,7 @@ static int _fortuna_reseed(prng_state *prng)
   @param prng     The PRNG to import
   @return CRYPT_OK if successful
 */
-static int _fortuna_update_seed(const unsigned char *in, unsigned long inlen, prng_state *prng)
+int fortuna_update_seed(const unsigned char *in, unsigned long inlen, prng_state *prng)
 {
    int           err;
    unsigned char tmp[MAXBLOCKSIZE];
@@ -481,7 +481,7 @@ int fortuna_import(const unsigned char *in, unsigned long inlen, prng_state *prn
       return err;
    }
 
-   if ((err = _fortuna_update_seed(in, inlen, prng)) != CRYPT_OK) {
+   if ((err = fortuna_update_seed(in, inlen, prng)) != CRYPT_OK) {
       return err;
    }