clang-tidy: sync argument names in prototype and definition

Discovered with clang-tidy checker
`readability-inconsistent-declaration-parameter-name`.

Also:
- do not enforce the above because of inconsistencies still present
  between public API prototypes and definitions. (Also betwen man page
  protos, and man page examples, and other parts of the code, e.g.
  `easy` vs `curl` vs `d` vs `handle`) Perhaps subject for a future
  effort:
  https://github.com/curl/curl/actions/runs/22166472728/job/64094691653
- enable and fix `readability-named-parameter` where missing.

Refs:
https://clang.llvm.org/extra/clang-tidy/checks/readability/inconsistent-declaration-parameter-name.html
https://clang.llvm.org/extra/clang-tidy/checks/readability/named-parameter.html

Closes #20624

lib/ftplistparser.h

@@ -37,7 +37,7 @@ CURLcode Curl_ftp_parselist_geterror(struct ftp_parselist_data *pl_data);
 
 struct ftp_parselist_data *Curl_ftp_parselist_data_alloc(void);
 
-void Curl_ftp_parselist_data_free(struct ftp_parselist_data **pl_data);
+void Curl_ftp_parselist_data_free(struct ftp_parselist_data **parserp);
 
 /* list of wildcard process states */
 typedef enum {