x86: intel-mid: Add section for sfi device table

When Intel mid uses SFI table to enumerate devices, it requires an extra
device table with further information about how to probe such devices.

This patch creates a section where the device table will stay if
CONFIG_X86_INTEL_MID is selected.

Signed-off-by: David Cohen <david.a.cohen@linux.intel.com>
Link: http://lkml.kernel.org/r/1382049336-21316-12-git-send-email-david.a.cohen@linux.intel.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>