bsps/powerpc: Delete bsp_exceptions_in_RAM

Delete ppc_exc_vector_base.  Add and use
ppc_exc_initialize_with_vector_base().
bsps: Move bsp_generic_fatal_code to new file

Add bsp_generic_fatal().
bsps: Add fatal errors for shared console driver
bsps: Do not use printk() in shared console driver
bsps: Remove debug output in shared console driver
bsps: Use CONSOLE_DEVICE_NAME
libchip/serial: Fix warning
IMFS: Fix reference count for debug enabled
score: _Heap_Protection_free_all_delayed_blocks()

Add and use _Heap_Protection_free_all_delayed_blocks() to prevent
test suite failures if RTEMS_DEBUG is defined.
arm: Fix default exception prologues