Rename struct avl to avl_element and the typedef to avl_t (#10735)

Before:

```
struct foobar {
    avl avl;
    ...
}
```

After:

```
struct foobar {
    avl_t avl;
    ...
};
```

Which makes figuring out the type from field name easier.

4 files changed, 7 insertions, 7 deletions

diff --git a/registry/registry_person.c b/registry/registry_person.c
index 268b0bd136..fae1520c4f 100644
--- a/registry/registry_person.c
+++ b/registry/registry_person.c
@@ -32,7 +32,7 @@ inline REGISTRY_PERSON_URL *registry_person_url_index_find(REGISTRY_PERSON *p, c
 
 inline REGISTRY_PERSON_URL *registry_person_url_index_add(REGISTRY_PERSON *p, REGISTRY_PERSON_URL *pu) {
     debug(D_REGISTRY, "Registry: registry_person_url_index_add('%s', '%s')", p->guid, pu->url->url);
-    REGISTRY_PERSON_URL *tpu = (REGISTRY_PERSON_URL *)avl_insert(&(p->person_urls), (avl *)(pu));
+    REGISTRY_PERSON_URL *tpu = (REGISTRY_PERSON_URL *)avl_insert(&(p->person_urls), (avl_t *)(pu));
     if(tpu != pu)
         error("Registry: registry_person_url_index_add('%s', '%s') already exists as '%s'", p->guid, pu->url->url, tpu->url->url);
 
@@ -41,7 +41,7 @@ inline REGISTRY_PERSON_URL *registry_person_url_index_add(REGISTRY_PERSON *p, RE
 
 inline REGISTRY_PERSON_URL *registry_person_url_index_del(REGISTRY_PERSON *p, REGISTRY_PERSON_URL *pu) {
     debug(D_REGISTRY, "Registry: registry_person_url_index_del('%s', '%s')", p->guid, pu->url->url);
-    REGISTRY_PERSON_URL *tpu = (REGISTRY_PERSON_URL *)avl_remove(&(p->person_urls), (avl *)(pu));
+    REGISTRY_PERSON_URL *tpu = (REGISTRY_PERSON_URL *)avl_remove(&(p->person_urls), (avl_t *)(pu));
     if(!tpu)
         error("Registry: registry_person_url_index_del('%s', '%s') deleted nothing", p->guid, pu->url->url);
     else if(tpu != pu)
diff --git a/registry/registry_person.h b/registry/registry_person.h
index 9a4aa959b9..42419bfe9b 100644
--- a/registry/registry_person.h
+++ b/registry/registry_person.h
@@ -10,7 +10,7 @@
 
 // for each PERSON-URL pair we keep this
 struct registry_person_url {
-    avl avl;                    // binary tree node
+    avl_t avl;                  // binary tree node
 
     REGISTRY_URL *url;          // de-duplicated URL
     REGISTRY_MACHINE *machine;  // link the MACHINE of this URL
diff --git a/registry/registry_url.c b/registry/registry_url.c
index 9ac3ce10c5..559799d8fe 100644
--- a/registry/registry_url.c
+++ b/registry/registry_url.c
@@ -13,11 +13,11 @@ int registry_url_compare(void *a, void *b) {
 }
 
 inline REGISTRY_URL *registry_url_index_add(REGISTRY_URL *u) {
-    return (REGISTRY_URL *)avl_insert(&(registry.registry_urls_root_index), (avl *)(u));
+    return (REGISTRY_URL *)avl_insert(&(registry.registry_urls_root_index), (avl_t *)(u));
 }
 
 inline REGISTRY_URL *registry_url_index_del(REGISTRY_URL *u) {
-    return (REGISTRY_URL *)avl_remove(&(registry.registry_urls_root_index), (avl *)(u));
+    return (REGISTRY_URL *)avl_remove(&(registry.registry_urls_root_index), (avl_t *)(u));
 }
 
 REGISTRY_URL *registry_url_get(const char *url, size_t urllen) {
@@ -33,7 +33,7 @@ REGISTRY_URL *registry_url_get(const char *url, size_t urllen) {
     strncpyz(n->url, url, n->len);
     n->hash = simple_hash(n->url);
 
-    REGISTRY_URL *u = (REGISTRY_URL *)avl_search(&(registry.registry_urls_root_index), (avl *)n);
+    REGISTRY_URL *u = (REGISTRY_URL *)avl_search(&(registry.registry_urls_root_index), (avl_t *)n);
     if(!u) {
         debug(D_REGISTRY, "Registry: registry_url_get('%s', %zu): allocating %zu bytes", url, urllen, sizeof(REGISTRY_URL) + urllen);
         u = callocz(1, sizeof(REGISTRY_URL) + urllen); // no need for +1, 1 is already in REGISTRY_URL
diff --git a/registry/registry_url.h b/registry/registry_url.h
index c684f1c35e..0cc364fdfe 100644
--- a/registry/registry_url.h
+++ b/registry/registry_url.h
@@ -12,7 +12,7 @@
 // we store them here and we keep pointers elsewhere
 
 struct registry_url {
-    avl avl;
+    avl_t avl;
     uint32_t hash;  // the index hash
 
     uint32_t links; // the number of links to this URL - when none is left, we free it