Refactor _Cget() to invoke _NanoFatalErrorHandler()

It is a fatal error if the microkernel is configured with either too few
command packets or too few timer packets.

NOTE: During this refactoring of _Cget(), not only is it renamed to
_nano_fiber_lifo_get_panic(), but it is moved into "nano_lifo.c".

Change-Id: I1d866cda1b444da04877f7eda03762b6e83c9a6f
Signed-off-by: Peter Mitsis <peter.mitsis@windriver.com>
4 files changed