autotools: add support for mingw UWP builds

To match cmake builds.

- GHA/windows: allow autotools UWP builds.
- detect UWP and add to `buildinfo.txt`.
  Consider it enabled if `CPPFLAGS` contains `-DWINSTORECOMPAT`.
- disable telnet with UWP.
- enable Unicode with UWP.
- do not use `wldap32` with UWP.
- do not enable `USE_WIN32_CRYPTO` with UWP.
- make sure to link to `ws2_32` in UWP builds.
  To fix `undefined reference to `in6addr_any'` when linking
  `tests/server` programs. More in the comment.

Closes #16020

acinclude.m4

@@ -1413,7 +1413,7 @@ AC_DEFUN([CURL_CHECK_WIN32_CRYPTO], [
   AC_REQUIRE([CURL_CHECK_NATIVE_WINDOWS])dnl
   AC_MSG_CHECKING([whether build target supports Win32 crypto API])
   curl_win32_crypto_api="no"
-  if test "$curl_cv_native_windows" = "yes"; then
+  if test "$curl_cv_native_windows" = "yes" -a "$curl_cv_winuwp" != "yes"; then
     AC_COMPILE_IFELSE([
       AC_LANG_PROGRAM([[
         #undef inline
@@ -1536,6 +1536,9 @@ AC_DEFUN([CURL_PREPARE_BUILDINFO], [
         curl_pflags="${curl_pflags} BSD";;
     esac
   fi
+  if test "$curl_cv_winuwp" = 'yes'; then
+    curl_pflags="${curl_pflags} UWP"
+  fi
   if test "$curl_cv_cygwin" = 'yes'; then
     curl_pflags="${curl_pflags} CYGWIN"
   fi