Some utils, like dmidecode and smbios, need to access SMBIOS entry
table area in order to get information like SMBIOS version, size, etc.
Currently it's done via /dev/mem. But for situation when /dev/mem
usage is disabled, the utils have to use dmi sysfs instead, which
doesn't represent SMBIOS entry and adds code/delay redundancy when direct
access for table is needed.

So this patch creates dmi/tables and adds SMBIOS entry point to allow
utils in question to work correctly without /dev/mem. Also patch adds
raw dmi table to simplify dmi table processing in user space, as
proposed by Jean Delvare.

Tested-by: Roy Franz <roy.franz@linaro.org>
Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@globallogic.com>
Signed-off-by: Jean Delvare <jdelvare@suse.de>