Allow device admin policy to override policy boolean state.

Prior code only allowed a false to true transition for a device
admin policy. This was to ensure that a default true was always
upheld. Reverse this and allow a device admin policy to take over
the setting of all booleans; even those set by the init.rc.

Change-Id: I64ae4d397a8118614c83fa611f0191e2f934dade
Signed-off-by: rpcraig <rpcraig@tycho.ncsc.mil>