Replace most uses of assert by ovs_assert.

This is a straight search-and-replace, except that I also removed #include
<assert.h> from each file where there were no assert calls left.

Signed-off-by: Ben Pfaff <blp@nicira.com>
Acked-by: Ethan Jackson <ethan@nicira.com>

lib/netlink-notifier.c

@@ -18,7 +18,6 @@
 
 #include "netlink-notifier.h"
 
-#include <assert.h>
 #include <errno.h>
 #include <poll.h>
 #include <stdlib.h>
@@ -87,7 +86,7 @@ void
 nln_destroy(struct nln *nln)
 {
     if (nln) {
-        assert(list_is_empty(&nln->all_notifiers));
+        ovs_assert(list_is_empty(&nln->all_notifiers));
         nl_sock_destroy(nln->notify_sock);
         free(nln);
     }