selinux: Fix ceph-iscsi etc access

selinux: Fix ceph-iscsi etc access

This fixes the selinux errors like this for /etc/target

-----------------------------------
Additional Information:
Source Context                system_u:system_r:ceph_t:s0
Target Context                system_u:object_r:targetd_etc_rw_t:s0
Target Objects                target [ dir ]
Source                        rbd-target-api
Source Path                   rbd-target-api
Port                          <Unknown>
Host                          ans8
Source RPM Packages
Target RPM Packages
Policy RPM                    selinux-policy-3.14.3-20.el8.noarch
Selinux Enabled               True
Policy Type                   targeted
Enforcing Mode                Enforcing
Host Name                     ans8
Platform                      Linux ans8 4.18.0-147.el8.x86_64 #1 SMP
Thu Sep 26
                              15:52:44 UTC 2019 x86_64 x86_64
Alert Count                   1
First Seen                    2020-01-08 18:39:48 EST
Last Seen                     2020-01-08 18:39:48 EST
Local ID                      9a13ee18-eaf2-4f2a-872f-2809ee4928f6

Raw Audit Messages
type=AVC msg=audit(1578526788.148:69): avc:  denied  { search } for
pid=995 comm="rbd-target-api" name="target" dev="sda1" ino=52198
scontext=system_u:system_r:ceph_t:s0
tcontext=system_u:object_r:targetd_etc_rw_t:s0 tclass=dir permissive=1

Hash: rbd-target-api,ceph_t,targetd_etc_rw_t,dir,search

which are a result of the rtslib library the ceph-iscsi daemons use
accessing /etc/target to read/write a file which stores meta data the
target uses.

Signed-off-by: Mike Christie <mchristi@redhat.com>