[MTE] Add memtag sysprop sepolicy.
These flags should be writeable to the shell for both root and non-root
users. They should be readable everywhere, as they're read in libc
during initialization (and there's nothing secret to hide). We just
don't want to allow apps to set these properties.
These properties are non-persistent, are for local developer debugging
only.
Bug: 135772972
Bug: 172365548
Test: `adb shell setprop memtag.123 0` in non-root shell succeeds.
Change-Id: If9ad7123829b0be27c29050f10081d2aecdef670
6 files changed