imap-send: display port alongwith host when git credential is invoked

When requesting for passsword, git credential helper used to display
only the host name. For example:

    Password for 'imaps://gargaditya08%40live.com@outlook.office365.com':

Now, it will display the port along with the host name:

    Password for 'imaps://gargaditya08%40live.com@outlook.office365.com:993':

This has been done to make credential helpers more specific for ports.
Also, this behaviour will also mimic git send-email, which displays
the port along with the host name when requesting for a password.

Signed-off-by: Aditya Garg <gargaditya08@live.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Author: AdityaGarg8

imap-send.c

@@ -1082,7 +1082,7 @@ static void server_fill_credential(struct imap_server_conf *srvc, struct credent
 		return;
 
 	cred->protocol = xstrdup(srvc->use_ssl ? "imaps" : "imap");
-	cred->host = xstrdup(srvc->host);
+	cred->host = xstrfmt("%s:%d", srvc->host, srvc->port);
 
 	cred->username = xstrdup_or_null(srvc->user);
 	cred->password = xstrdup_or_null(srvc->pass);