x86: DMI match for the Sony VGN-Z540N as it needs BIOS reboot,
see:

  http://bugzilla.kernel.org/show_bug.cgi?id=12901

[ Impact: fix hung reboot on certain systems ]
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Cc: Len Brown <lenb@kernel.org>
LKML-Reference: <1242963350.32574.53.camel@rzhang-dt>
Signed-off-by: Ingo Molnar <mingo@elte.hu>