Convert all selinux_android_restorecon and _setfilecon calls to new API.

libselinux selinux_android_restorecon API is changing to the more
general interface with flags and dropping the older variants.

Also get rid of the old, no longer used selinux_android_setfilecon API
and rename selinux_android_setfilecon2 to it as it is the only API in use.

Change-Id: Iecc2aeafe87fe43f1554b92f7fe77a2aa2d1b771
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>