refactor(plat/host/common): extract host_utils parts to its own library

This allows RMM apps to use sysregs and spinlock without pulling in
rmm-host-common.

Change-Id: I962f2de687fa4f14b5e94f8686d7b13b7cd006c6
Signed-off-by: Mate Toth-Pal <mate.toth-pal@arm.com>
18 files changed