tools/wmi: add a sample for dell smbios communication over WMI

This application uses the character device /dev/wmi/dell-smbios
to perform SMBIOS communications from userspace.

It offers demonstrations of a few simple tasks:
 - Running a class/select command
 - Querying a token value
 - Activating a token

Signed-off-by: Mario Limonciello <mario.limonciello@dell.com>
Reviewed-by: Edward O'Callaghan <quasisec@google.com>
Signed-off-by: Darren Hart (VMware) <dvhart@infradead.org>