clang-tidy: enable more checks, fix fallouts

- enable three checks:
  - bugprone-invalid-enum-default-initialization
  - bugprone-sizeof-expression
  - readability-inconsistent-declaration-parameter-name (strict)
- fix remaining discrepancies with arg names in prototypes
  and implementation, in strict mode.
- document reason for some checks tested but not enabled.

Closes #20794

docs/libcurl/curl_easy_header.md

@@ -26,7 +26,7 @@ curl_easy_header - get an HTTP header
 
 CURLHcode curl_easy_header(CURL *easy,
                            const char *name,
-                           size_t index,
+                           size_t nameindex,
                            unsigned int origin,
                            int request,
                            struct curl_header **hout);
@@ -38,10 +38,10 @@ curl_easy_header(3) returns a pointer to a "curl_header" struct in **hout**
 with data for the HTTP response header *name*. The case insensitive
 null-terminated header name should be specified without colon.
 
-*index* 0 means asking for the first instance of the header. If the returned
-header struct has **amount** set larger than 1, it means there are more
-instances of the same header name available to get. Asking for a too big index
-makes **CURLHE_BADINDEX** get returned.
+*nameindex* 0 means asking for the first instance of the header. If the
+returned header struct has **amount** set larger than 1, it means there are
+more instances of the same header name available to get. Asking for a too big
+index makes **CURLHE_BADINDEX** get returned.
 
 The *origin* argument is for specifying which headers to receive, as a single
 HTTP transfer might provide headers from several different places and they may

docs/libcurl/curl_easy_pause.md

@@ -21,7 +21,7 @@ curl_easy_pause - pause and unpause a connection
 ~~~c
 #include <curl/curl.h>
 
-CURLcode curl_easy_pause(CURL *handle, int bitmask);
+CURLcode curl_easy_pause(CURL *handle, int action);
 ~~~
 
 # DESCRIPTION
@@ -54,7 +54,7 @@ A paused transfer is excluded from low speed cancels via the
 CURLOPT_LOW_SPEED_LIMIT(3) option and unpausing a transfer resets the
 time period required for the low speed limit to be met.
 
-The **bitmask** argument is a set of bits that sets the new state of the
+The **action** argument is a set of bits that sets the new state of the
 connection. The following bits can be used:
 
 ## CURLPAUSE_RECV

docs/libcurl/curl_multi_timeout.md

@@ -37,7 +37,7 @@ curl_multi_socket_action(3) function with the **sockfd** argument set
 to CURL_SOCKET_TIMEOUT, or call curl_multi_perform(3) if you are using
 the simpler and older multi interface approach.
 
-The timeout value returned in the long **timeout** points to, is in number
+The timeout value returned in the long **timeout_ms** points to, is in number
 of milliseconds at this moment. If 0, it means you should proceed immediately
 without waiting for anything. If it returns -1, there is no timeout at all set.