Suppress mediaprover access to certain cache dirs

avc: denied { getattr } for comm="sAsyncHandlerTh"
path="/data/cache/recovery" dev="sda13" ino=7086082
scontext=u:r:mediaprovider:s0:c512,c768
tcontext=u:object_r:cache_recovery_file:s0 tclass=dir
avc: denied { getattr } for path="/data/cache/backup"
scontext=u:r:mediaprovider:s0:c512,c768
tcontext=u:object_r:cache_private_backup_file:s0 tclass=dir

Bug: 63038506
Bug: 35197529
Test: build police
Change-Id: I51624c255e622bf712d41ca1bbf190ec3e4fefae
(cherry picked from commit fcf1b2083935bd298a2ece8d6d0c18712865a04b)