haldomain: search for passthrough hals

Bug: 34366227
Test: passthrough services successfully found
Change-Id: If2cad09edc42f01cc5a444229758ecdfe2017cf2

private/haldomain.te

@@ -3,3 +3,6 @@
 ###
 
 hwbinder_use(haldomain)
+
+# find passthrough hals
+allow haldomain system_file:dir r_dir_perms;

public/hal_camera.te

 hwbinder_use(hal_camera)
 binder_call(hal_camera, cameraserver)
 
-allow hal_camera system_file:dir { open read };
-
 # access /data/misc/camera
 allow hal_camera camera_data_file:dir create_dir_perms;
 allow hal_camera camera_data_file:file create_file_perms;

public/hal_fingerprint.te

-# Scan through /system/lib64/hw looking for installed HALs
-allow hal_fingerprint system_file:dir r_dir_perms;
-
 # allow HAL module to read dir contents
 allow hal_fingerprint fingerprintd_data_file:file create_file_perms;