OS400 fails to build 7.86.0, curl_socklen_t referenced before its defined

[jonrumsey]

I did this

Attempted to build curl 7.86.0 on IBM i V7R4M0

CZM1003:  /curl/src/curl-7.86.0/lib/setup-os400.h, 54.31: CZM0046(30) Syntax error.
CZS1601:  Program CHKSTRINGS is not created because statement errors occurred.
CZM1613:  The compilation failed.

The order of the includes in curl_setup.h was changed by
#9453
so that curl.h is now included after platform specific headers (i.e. setup-os400.h) and the typedef of curl_socklen_t is now after being referenced in a prototype like;

   53       |extern int Curl_getnameinfo_a(const struct sockaddr *sa,                 
   54       |                              curl_socklen_t salen,                      
===========> ..............................a..........................................
*=SEVERE==========> a - CZM0046  Syntax error.                                        
   55       |                              char *nodename, curl_socklen_t nodenamelen,
   56       |                              char *servname, curl_socklen_t servnamelen,
   57       |                              int flags);                                

I think the right fix here is to keep the order of the includes but change the prototype of the platform specific ASCII wrapper to use the platform socklen_t, to match the prototype for getnameinfo, and not use the curl_socklen_t.

I expected the following

Clean build

curl/libcurl version

curl 7.86.0

operating system

IBM i V7R4M0