Adding a new value to cookie

This new value will be used by javascript in phosphor-webui
to perform login-less authentication.

Tested:
	Manually tests were performed on Chrome browser.
	Having enabled and configured mTLS user is able
	to authenticate with proper certificates.
	The login page is not displayed unless user logs out.

Appropriate phosphor-webui changes can be found here:
   https://gerrit.openbmc-project.xyz/c/openbmc/phosphor-webui/+/27851

Signed-off-by: Zbigniew Kurzynski <zbigniew.kurzynski@intel.com>
Change-Id: Iac76459e1843a5c8bd2287c6e078319aebedfdcc
diff --git a/http/http_connection.h b/http/http_connection.h
index 0b15616..cce4a54 100644
--- a/http/http_connection.h
+++ b/http/http_connection.h
@@ -540,7 +540,8 @@
                                       "XSRF-TOKEN=" + sp->csrfToken +
                                           "; Secure\r\nSet-Cookie: SESSION=" +
                                           sp->sessionToken +
-                                          "; Secure; HttpOnly");
+                                          "; Secure; HttpOnly\r\nSet-Cookie: "
+                                          "IsAuthenticated=true; Secure");
                         BMCWEB_LOG_DEBUG
                             << this << " TLS session: " << sp->uniqueId
                             << " with cookie will be used for this request.";