src: use curlx_dyn_ prefix, not Curl_dyn_

Closes #16658
diff --git a/src/tool_cfgable.c b/src/tool_cfgable.c
index 3de7cbd..2828f97 100644
--- a/src/tool_cfgable.c
+++ b/src/tool_cfgable.c
@@ -61,7 +61,7 @@
   Curl_safefree(config->cookiejar);
   curl_slist_free_all(config->cookiefiles);
 
-  Curl_dyn_free(&config->postdata);
+  curlx_dyn_free(&config->postdata);
   Curl_safefree(config->query);
   Curl_safefree(config->referer);
 
diff --git a/src/tool_ssls.c b/src/tool_ssls.c
index 2a7d81d..8237665 100644
--- a/src/tool_ssls.c
+++ b/src/tool_ssls.c
@@ -86,7 +86,7 @@
     ++i;
     curl_free(shmac);
     curl_free(sdata);
-    line = Curl_dyn_ptr(&buf);
+    line = curlx_dyn_ptr(&buf);
 
     c = memchr(line, ':', strlen(line));
     if(!c) {
diff --git a/src/var.c b/src/var.c
index 70dc4fe..1a0e71e 100644
--- a/src/var.c
+++ b/src/var.c
@@ -471,7 +471,7 @@
     struct dynbuf fname;
     line++;
 
-    Curl_dyn_init(&fname, MAX_FILENAME);
+    curlx_dyn_init(&fname, MAX_FILENAME);
 
     use_stdin = !strcmp(line, "-");
     if(use_stdin)
@@ -490,7 +490,7 @@
       if(clen)
         contalloc = TRUE;
     }
-    Curl_dyn_free(&fname);
+    curlx_dyn_free(&fname);
     if(!use_stdin && file)
       fclose(file);
     if(err)