Add the function osThreadGetInfo to allow various Thread information
to be queried. This includes stack size and maximum stack usage among
other things.
Note - for Cortex-A devices the worst case stack usage is not
available.
Prevent a switch to a NULL target thread by setting the new task to run
to be the idle task. Otherwise, we get nasty usage fault because we
would be returning from the rt_sys_init SVC with a PSP of 0x20.
Add the OsEventObserver mechanism. A client interested in receiving
notifications on certain OS events can register to receive notifications
with osRegisterForOsEvents. This is useful for clients like the secure
memory allocator, which observes thread switching events in order to swap
in and out different memory allocator objects.
Russ Butler
Jaeden Amero
Mihail Stoyanov