[ros-diffs] [ion] 26671: - Remove/deprecate some certain chunks of Cm which are not critical to booting and not even to applications (such as NtSaveKey, which didn't even have NtRestoreKey) and mark them as unimplemented functions. - This doesn't do much but clean up some of our code to make it easier to see what the critical parts are and reduce bug surface exposure. - Move and slightly reformat (without touching any of the actual code) registry callback/notification code to cmhook.c.