fix(rmm): changes for Release build and logging

This patch sets default Release build LOG_LEVEL to
20 (LOG_LEVEL_NOTICE) to match TF-A code.
Function 'assert_cpu_slots_empty()' replaced
with 'check_cpu_slots_empty()' returning
boolean value

Change-Id: I544143510325636ba784e476dbb83b923013b0e2
Signed-off-by: AlexeiFedorov <Alexei.Fedorov@arm.com>
4 files changed