MAINTAINERS: update web URL for iwlwifi

The current URL mentioned in iwlwifi's W entry is outdated and
currently pointing to a dead link.  Change it so that it points to the
correct Wiki page directly.
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

MAINTAINERS

@@ -8684,7 +8684,7 @@ M:	Emmanuel Grumbach <emmanuel.grumbach@intel.com>
 M:	Luca Coelho <luciano.coelho@intel.com>
 M:	Intel Linux Wireless <linuxwifi@intel.com>
 L:	linux-wireless@vger.kernel.org
-W:	http://intellinuxwireless.org
+W:	https://wireless.wiki.kernel.org/en/users/drivers/iwlwifi
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/iwlwifi/iwlwifi.git
 S:	Supported
 F:	drivers/net/wireless/intel/iwlwifi/