libcurl 7.56.0 deprecations

The usage of curl in the coveralls-writer gives a bunch of deprecation warnings when compiled against recent libcurl.
It would appear some of the CURLFORM things have been replaced with curl_mime_* functionality.
/var/tmp/portage/dev-util/kcov-42/work/kcov-42/src/writers/coveralls-writer.cc: In member function ‘bool CurlConnectionHandler::talk(const std::string&)’:
/var/tmp/portage/dev-util/kcov-42/work/kcov-42/src/writers/coveralls-writer.cc:65:33: warning: ‘CURLFORM_COPYNAME’ is deprecated: since 7.56.0. Use curl_mime_name() [-Wdeprecated-declarations]
   65 |                                 CURLFORM_COPYNAME, "json_file",
      |                                 ^~~~~~~~~~~~~~~~~
In file included from /var/tmp/portage/dev-util/kcov-42/work/kcov-42/src/writers/coveralls-writer.cc:16:
/usr/include/curl/curl.h:2510:3: note: declared here
 2510 |   CURLFORM_COPYNAME        CURL_DEPRECATED(7.56.0, "Use curl_mime_name()"),
      |   ^~~~~~~~~~~~~~~~~
/var/tmp/portage/dev-util/kcov-42/work/kcov-42/src/writers/coveralls-writer.cc:66:33: warning: ‘CURLFORM_FILE’ is deprecated: since 7.56.0. Use curl_mime_filedata() [-Wdeprecated-declarations]
   66 |                                 CURLFORM_FILE, fileName.c_str(),
      |                                 ^~~~~~~~~~~~~
/usr/include/curl/curl.h:2519:3: note: declared here
 2519 |   CURLFORM_FILE            CURL_DEPRECATED(7.56.0, "Use curl_mime_filedata()"),
      |   ^~~~~~~~~~~~~
/var/tmp/portage/dev-util/kcov-42/work/kcov-42/src/writers/coveralls-writer.cc:63:29: warning: ‘CURLFORMcode curl_formadd(curl_httppost**, curl_httppost**, ...)’ is deprecated: since 7.56.0. Use curl_mime_init() [-Wdeprecated-declarations]
   63 |                 curl_formadd(&formpost,
      |                 ~~~~~~~~~~~~^~~~~~~~~~~
   64 |                                 &lastptr,
      |                                 ~~~~~~~~~
   65 |                                 CURLFORM_COPYNAME, "json_file",
      |                                 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   66 |                                 CURLFORM_FILE, fileName.c_str(),
      |                                 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   67 |                                 CURLFORM_END);
      |                                 ~~~~~~~~~~~~~
/usr/include/curl/curl.h:2585:1: note: declared here
 2585 | curl_formadd(struct curl_httppost **httppost,
      | ^~~~~~~~~~~~
/var/tmp/portage/dev-util/kcov-42/work/kcov-42/src/writers/coveralls-writer.cc:69:42: warning: ‘CURLOPT_HTTPPOST’ is deprecated: since 7.56.0. Use CURLOPT_MIMEPOST [-Wdeprecated-declarations]
   69 |                 curl_easy_setopt(m_curl, CURLOPT_HTTPPOST, formpost);
      |                                          ^~~~~~~~~~~~~~~~
/usr/include/curl/curl.h:1199:3: note: declared here
 1199 |   CURLOPTDEPRECATED(CURLOPT_HTTPPOST, CURLOPTTYPE_OBJECTPOINT, 24,
      |   ^~~~~~~~~~~~~~~~~
/var/tmp/portage/dev-util/kcov-42/work/kcov-42/src/writers/coveralls-writer.cc:73:30: warning: ‘void curl_formfree(curl_httppost*)’ is deprecated: since 7.56.0. Use curl_mime_free() [-Wdeprecated-declarations]
   73 |                 curl_formfree(formpost);
      |                 ~~~~~~~~~~~~~^~~~~~~~~~
/usr/include/curl/curl.h:2621:1: note: declared here
 2621 | curl_formfree(struct curl_httppost *form);
      | ^~~~~~~~~~~~~
See:
SimonKagstrom / kcov

libcurl 7.56.0 deprecations #409
