Enable the spm_mm framework for the qemu_sbsa platform.
Memory layout required for spm_mm is created in secure SRAM.

Co-developed-by: Fu Wei <fu.wei@linaro.org>
Signed-off-by: Fu Wei <fu.wei@linaro.org>
Signed-off-by: Masahisa Kojima <masahisa.kojima@linaro.org>
Change-Id: I104a623e8bc1e44d035b95f014a13b3f8b33a62a