smbios: Add more properties

The current tables only support a subset of the available fields defined
by the SMBIOS spec. Add a few more.

We could use CONFIG_SYS_CPU or CONFIG_SYS_SOC as a default for family, but
the meaning of that value relates more to the whole system rather than
just the SoC.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>