smbios: type2: contained object handles

The type 2 structure must include information about the contained objects.
It is fine to set the number of contained object handles to 0.

Add the missing field.

Fixes: 721e992a ("x86: Add SMBIOS table support")
Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>