Add support for reloading policy from /data/system.

To support runtime policy management, add support for reloading
policy from /data/system.  This can be triggered by setting the
selinux.loadpolicy property to 1, whether from init.rc after
mounting /data or from the system_server (e.g. upon invocation of
a new device admin API for provisioning policy). ueventd and
installd are restarted upon policy reloads to pick up the new
policy configurations relevant to their operation.

Change-Id: I97479aecef8cec23b32f60e09cc778cc5520b691
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
diff --git a/init/init.h b/init/init.h
index 58bbbfe..e2d990e 100644
--- a/init/init.h
+++ b/init/init.h
@@ -138,6 +138,7 @@
 
 #ifdef HAVE_SELINUX
 extern struct selabel_handle *sehandle;
+extern int selinux_reload_policy(void);
 #endif
 
 #endif	/* _INIT_INIT_H */