Set SELinux security contexts correctly for init and services.

Otherwise everything is left running in the kernel domain when
booting recovery.

Change-Id: Ie3d86547d5be0b68dd1875a97afe1e00fc3e4da1
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Add seclabel to minivold

Change-Id: Ia5662f4543e4fbb32b02216b64a2f261e22beb25