Allow iio-sensor-proxy read iio devices

The commit addresses the following AVC denial:
type=AVC msg=audit(1736441634.931:680): avc:  denied  { read } for  pid=1121 comm="iio-sensor-prox" name="iio:device0" dev="devtmpfs" ino=1088 scontext=system_u:system_r:iiosensorproxy_t:s0 tcontext=system_u:object_r:device_t:s0 tclass=chr_file permissive=1

Resolves: rhbz#2336620

policy/modules/contrib/iiosensorproxy.te

@@ -13,6 +13,7 @@ allow iiosensorproxy_t self:capability2 bpf;
 allow iiosensorproxy_t self:netlink_kobject_uevent_socket create_socket_perms;
 allow iiosensorproxy_t self:unix_dgram_socket create_socket_perms;
 
+dev_read_iio_dev(iiosensorproxy_t)
 dev_read_input(iiosensorproxy_t)
 dev_create_sysfs_files(iiosensorproxy_t)
 dev_rw_sysfs(iiosensorproxy_t)