Add error handling for curl_easy_getinfo

Set response explicitly in case of curl_easy_getinfo error (though in
practice the response isn't modified and so program behavior is the
same as before this change).

Signed-off-by: William Douglas <william.douglas@intel.com>

src/swupd_lib/curl.c

@@ -457,7 +457,9 @@ enum download_status process_curl_error_codes(int curl_ret, CURL *curl_handle)
 		}
 	} else { /* download failed but let our caller do it */
 		long response = 0;
-		curl_easy_getinfo(curl_handle, CURLINFO_RESPONSE_CODE, &response);
+		if (curl_easy_getinfo(curl_handle, CURLINFO_RESPONSE_CODE, &response) != CURLE_OK) {
+			response = -1; // Force error
+		}
 		debug("Curl - process_curl_error_codes: curl_ret = %d, response = %ld\n", curl_ret, response);
 		switch (response) {
 		case 403: