Grant update_verifier the permissions to read /data/ota_package/
and the blocks on system partition.

The denial messages:
update_verifier: type=1400 audit(0.0:29): avc: denied { read } for name="care_map.txt" dev="sda35"
ino=1368066 scontext=u:r:update_verifier:s0 tcontext=u:object_r:ota_package_file:s0 tclass=file permissive=1

update_verifier: type=1400 audit(0.0:30): avc: denied { open } for path="/data/ota_package/care_map.txt" dev="sda35"
ino=1368066 scontext=u:r:update_verifier:s0 tcontext=u:object_r:ota_package_file:s0 tclass=file permissive=1

update_verifier: type=1400 audit(0.0:31): avc: denied { read } for name="sda33" dev="tmpfs" ino=5613
scontext=u:r:update_verifier:s0 tcontext=u:object_r:system_block_device:s0 tclass=blk_file permissive=1

update_verifier: type=1400 audit(0.0:32): avc: denied { open } for path="/dev/block/sda33" dev="tmpfs" ino=5613
scontext=u:r:update_verifier:s0 tcontext=u:object_r:system_block_device:s0 tclass=blk_file permissive=1

Test: On sailfish, update_verifier reads the blocks successfully during boot time.
Bug: 30020920

Change-Id: I10777c1e6ba649b82c4a73171124742edeb05997