build: update to not need _CRT_NONSTDC_NO_DEPRECATE with MSVC

Use non-deprecated CRT function variants on Windows.

- introduce `curlx_fdopen()`, `curlx_close()` and use them. Map them to
  non-deprecated, underscored, CRT functions on Windows.

- replace `close()` uses with either `sclose()` (for sockets) or
  `curlx_close()` (for files).

- map `fileno`, `unlink`, `isatty` to their non-deprecated, underscored,
  versions on Windows.

- tool_dirhie: map `mkdir` to `_mkdir` on Windows.

- easy: use `_strdup()` on Windows, regardless of how `HAVE_STRDUP` is
  set.

- cmake: assume `HAVE_STRDUP` on Windows. To allow dropping a detection
  hack using `_CRT_NONSTDC_NO_DEPRECATE` with MSVC. Windows always has
  `_strdup()` which the code uses, but also needs `HAVE_STRDUP` defined
  to disable curl's own `strdup()` implementation.

- curl_setup.h: drop `_CRT_NONSTDC_NO_DEPRECATE` as no longer necessary.

Closes #20212

src/tool_cb_wrt.c

@@ -89,7 +89,7 @@ bool tool_create_output_file(struct OutStruct *outs,
     if(fd != -1) {
       file = curlx_fdopen(fd, "wb");
       if(!file)
-        close(fd);
+        curlx_close(fd);
     }
   }
 

src/tool_dirhie.c

@@ -23,14 +23,13 @@
  ***************************************************************************/
 #include "tool_setup.h"
 
-#ifdef _WIN32
-#include <direct.h>
-#endif
-
 #include "tool_dirhie.h"
 #include "tool_msgs.h"
 
-#if defined(_WIN32) || (defined(MSDOS) && !defined(__DJGPP__))
+#ifdef _WIN32
+#  include <direct.h>
+#  define mkdir(x, y) _mkdir(x)
+#elif defined(MSDOS) && !defined(__DJGPP__)
 #  define mkdir(x, y) (mkdir)(x)
 #endif
 

src/tool_findfile.c

@@ -74,7 +74,7 @@ static char *checkhome(const char *home, const char *fname, bool dotscore)
       int fd = curlx_open(c, O_RDONLY);
       if(fd >= 0) {
         char *path = curlx_strdup(c);
-        close(fd);
+        curlx_close(fd);
         curl_free(c);
         return path;
       }

src/tool_getpass.c

@@ -187,7 +187,7 @@ char *getpass_r(const char *prompt, /* prompt to display */
   }
 
   if(STDIN_FILENO != fd)
-    close(fd);
+    curlx_close(fd);
 
   return password; /* return pointer to buffer */
 }

src/tool_operate.c

@@ -289,7 +289,7 @@ static CURLcode pre_transfer(struct per_transfer *per)
     {
       helpf("cannot open '%s'", per->uploadfile);
       if(per->infd != -1) {
-        close(per->infd);
+        curlx_close(per->infd);
         per->infd = STDIN_FILENO;
       }
       return CURLE_READ_ERROR;
@@ -621,7 +621,7 @@ static CURLcode post_per_transfer(struct per_transfer *per,
   else
 #endif
     if(per->infdopen)
-      close(per->infd);
+      curlx_close(per->infd);
 
   if(per->skip)
     goto skip;