Deprecate wait() in favour of acquire(), try_acquire(),
try_acquire_for() and try_acquire_until().
Brings Semaphore more into line with CMSIS-RTOS 2 (which uses "acquire"),
itself (as it has "release"), and other classes having "try", "try for"
and "try until".
Also steps away from vague "wait" term - the primary operation here is
to acquire the semaphore, and this will of course sleep.
Given the 64-bit timebase, add wait_until to Semaphore.
Naming is based on Thread::wait_until.
pthreads uses "timedwait", but that's not a good fit against our
existing wait() - pthreads only has an absolute-time wait, not relative.
Various RTOS classes were storing their CMSIS-RTOS creation attribute
structure as a member, when it's not required after construction. Reduce
memory by eliminating this member.
Before rtx 5, the max count on semaphores was UINT16_MAX, aftewards it
was decreased to 1024 with an assert on overflow.
This is especially problematic for semaphores used for signaling, since
there is no replacement currently available in C++.
Kevin Bracey
Martin Kojtal
Brendan McDonnell
Christopher Haster
Bartek Szatkowski
Sam Grove