Convert all zero-argument functions to '(void)'

Otherwise, in C, it becomes a K&R function declaration which doesn't actually
type-check the number of arguments.

Change-Id: I0731a9fefca46fb1c266bfb1c33d464cf451a22e
Reviewed-on: https://boringssl-review.googlesource.com/1582
Reviewed-by: Adam Langley <agl@google.com>
diff --git a/ssl/pqueue/pqueue.c b/ssl/pqueue/pqueue.c
index e8d0ac5..4c68cb1 100644
--- a/ssl/pqueue/pqueue.c
+++ b/ssl/pqueue/pqueue.c
@@ -87,7 +87,7 @@
   OPENSSL_free(item);
 }
 
-pqueue pqueue_new() {
+pqueue pqueue_new(void) {
   pqueue_s *pq = (pqueue_s *)OPENSSL_malloc(sizeof(pqueue_s));
   if (pq == NULL) {
     return NULL;