crypto: jitter - fix comments

One should not say "ec can be NULL" and then dereference it.
One cannot talk about the return value if the function returns void.
Signed-off-by: NAlexander E. Patrakov <patrakov@gmail.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

crypto/jitterentropy.c

@@ -172,7 +172,7 @@ static __u64 jent_loop_shuffle(struct rand_data *ec,
  * implies that careful retesting must be done.
  *
  * Input:
- * @ec entropy collector struct -- may be NULL
+ * @ec entropy collector struct
  * @time time stamp to be injected
  * @loop_cnt if a value not equal to 0 is set, use the given value as number of
  *	     loops to perform the folding
@@ -400,8 +400,8 @@ static void jent_gen_entropy(struct rand_data *ec)
  * primes the test if needed.
  *
  * Return:
- * 0 if FIPS test passed
- * < 0 if FIPS test failed
+ * returns normally if FIPS test passed
+ * panics the kernel if FIPS test failed
  */
 static void jent_fips_test(struct rand_data *ec)
 {