Add wakelock_use to slideshow.te to fix the following denial:
avc: denied { block_suspend } for pid=137 comm="slideshow" capability=36 scontext=u:r:slideshow:s0 tcontext=u:r:slideshow:s0 tclass=capability2 permissive=0
Change-Id: If84f167cd235e8196eadf3fb85cc725a5ea464e6
Add rules to allow /sbin/slideshow to access framebuffer and input
devices at early stages of boot, and rules to allow init to execute
the program (from init.rc using exec).
Needed by changes from
I58c79a7f3ac747eec0d73a10f018d3d8ade9df7d
Change-Id: I1d5018feb7025853f0bf81651f497fef8c3a6ab0