http: rename CURLOPT_FILE to CURLOPT_WRITEDATA

The CURLOPT_FILE name is an alias for CURLOPT_WRITEDATA, the
CURLOPT_WRITEDATA name has been preferred since curl 7.9.7, released
in May 2002[1].

1. https://curl.se/libcurl/c/CURLOPT_WRITEDATA.html

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/http.c b/http.c
index e944685..a0f169d 100644
--- a/http.c
+++ b/http.c
@@ -1769,7 +1769,7 @@ static int http_request(const char *url,
 		curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 1);
 	} else {
 		curl_easy_setopt(slot->curl, CURLOPT_NOBODY, 0);
-		curl_easy_setopt(slot->curl, CURLOPT_FILE, result);
+		curl_easy_setopt(slot->curl, CURLOPT_WRITEDATA, result);
 
 		if (target == HTTP_REQUEST_FILE) {
 			off_t posn = ftello(result);
@@ -2186,7 +2186,7 @@ struct http_pack_request *new_direct_http_pack_request(
 	}
 
 	preq->slot = get_active_slot();
-	curl_easy_setopt(preq->slot->curl, CURLOPT_FILE, preq->packfile);
+	curl_easy_setopt(preq->slot->curl, CURLOPT_WRITEDATA, preq->packfile);
 	curl_easy_setopt(preq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite);
 	curl_easy_setopt(preq->slot->curl, CURLOPT_URL, preq->url);
 	curl_easy_setopt(preq->slot->curl, CURLOPT_HTTPHEADER,
@@ -2357,7 +2357,7 @@ struct http_object_request *new_http_object_request(const char *base_url,
 
 	freq->slot = get_active_slot();
 
-	curl_easy_setopt(freq->slot->curl, CURLOPT_FILE, freq);
+	curl_easy_setopt(freq->slot->curl, CURLOPT_WRITEDATA, freq);
 	curl_easy_setopt(freq->slot->curl, CURLOPT_FAILONERROR, 0);
 	curl_easy_setopt(freq->slot->curl, CURLOPT_WRITEFUNCTION, fwrite_sha1_file);
 	curl_easy_setopt(freq->slot->curl, CURLOPT_ERRORBUFFER, freq->errorstr);