x86: consider modules when cutting off memory

x86: consider modules when cutting off memory

The code in question runs after module ranges got already removed from
the E820 table, so when determining the new maximum page/PDX we need to
explicitly take them into account.

Furthermore we need to round up the ending addresses here, in order to
fully cover eventual partial trailing pages.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Keir Fraser <keir@xen.org>
master commit: a5db2c7aab7a638d84f22ac8fe5089d81175438b
master date: 2013-11-18 13:57:20 +0100