SPM: Use global variables as ns agent stack

Use global arrays as stack of the ns agent partition instead
of the ER_INITIAL_PSP. The stack size related settings are
added into the 'config_impl.h' template file.

Change-Id: If8443c6fe02d3f1547c637bd51f0a7352aead0c1
Signed-off-by: Mingyang Sun <mingyang.sun@arm.com>
7 files changed