Restore recovery's ability to format cache and preserve logs

Commit b8b4f5d6 'Clean up old file-based OTA SELinux rules' removed
many permissions from recovery, a few of which are still required.
Restore these.

[ 2918.409108] type=1400 audit(2327427.540:159): avc:  denied
{ search } for  pid=339 comm="recovery" name="/" dev="mmcblk0p38"
ino=2 scontext=u:r:recovery:s0 tcontext=u:object_r:unlabeled:s0
tclass=dir permissive=0
[ 2586.563071] E:Failed to mount / create /cache/recovery: Permission
denied
[ 2586.780320] E:Can't open /cache/recovery/log: Permission denied
[ 2586.850399] E:Can't open /cache/recovery/last_log: Permission
denied
[ 2586.918979] E:Can't open /cache/recovery/last_install: Permission
denied

[   54.035867] type=1400 audit(59206654.526:12): avc:  denied  { chown }
for  pid=330 comm="recovery" capability=0  scontext=u:r:recovery:s0
tcontext=u:r:recovery:s0 tclass=capability permissive=0a

Bug: 70350029
Test: xunchang to test
Change-Id: I46ab049b8eb600b44c84a61777fade150cadd197