SFI: add platform-independent core support

drivers/sfi/sfi_core.c contains the generic SFI implementation.
It has a private header, sfi_core.h, for its own use and the
private use of future files in drivers/sfi/

Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

drivers/Makefile

diff --git a/drivers/Makefile b/drivers/Makefile
index bc4205d..ccfa259f 100644
--- a/drivers/Makefile
+++ b/drivers/Makefile
@@ -11,6 +11,7 @@
 obj-$(CONFIG_RAPIDIO)		+= rapidio/
 obj-y				+= video/
 obj-$(CONFIG_ACPI)		+= acpi/
+obj-$(CONFIG_SFI)		+= sfi/
 # PnP must come after ACPI since it will eventually need to check if acpi
 # was used and do nothing if so
 obj-$(CONFIG_PNP)		+= pnp/