* We are now *much* better at not reserving unnecessary
system MPU regions based on configuration. The #defines
for intent are now an enumerated type. As a bonus, the
implementation of _get_region_index_by_type() is much
simpler. Previously we were wasting regions for stack guard
and application memory if they were not configured.
* NXP MPU doesn't reserve the last region if HW stack
protection isn't enabled.
* Certain parts of the MPU code are now properly ifdef'd
based on configuration.
* THREAD_STACK_REGION and THREAD_STACK_USER_REGION was a
confusing construction and has now been replaced with
just THREAD_STACK_REGION, which represents the MPU region
for a user mode thread stack. Supervisor mode stacks
do not require an MPU region.
* The bounds of CONFIG_APPLICATION_MEMORY never changes
and we just do it once during initialization instead of
every context switch.
* Assertions have been added to catch out-of-bounds cases.
Fixes: #7384
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>