Allow some vold_prepare_subdirs denials.

This addresses the following denials:

avc: denied { fowner } for comm="rm" scontext=u:r:vold_prepare_subdirs:s0 tcontext=u:r:vold_prepare_subdirs:s0 tclass=capability
avc: denied { getattr } for comm="rm" scontext=u:r:vold_prepare_subdirs:s0 tcontext=u:object_r:storaged_data_file:s0 tclass=file
avc: denied { relabelfrom } for comm="vold_prepare_su" name="storaged" scontext=u:r:vold_prepare_subdirs:s0 tcontext=u:object_r:system_data_file:s0 tclass=dir
avc: denied { getattr } for comm="rm" scontext=u:r:vold_prepare_subdirs:s0 tcontext=u:object_r:system_data_file:s0 tclass=file

Bug: 77875245
Test: Boot device.
Test: Mislabel directories used by vold_prepare_subdirs, reboot, and
ensure it can relabel them without denials.
Test: Add user, reboot, delete user, reboot, observe no denials.

(cherry picked from commit 855dd5a8562494f78f99e5bd5096f617ac70438f)

Merged-In: Id67bc99f151a6ccb9619bbfb7080452956405121
Change-Id: Ic86be1e1afed37602255448e5700811d197403f9

private/vold_prepare_subdirs.te

@@ -7,13 +7,15 @@ allow vold_prepare_subdirs devpts:chr_file rw_file_perms;
 allow vold_prepare_subdirs vold:fd use;
 allow vold_prepare_subdirs vold:fifo_file { read write };
 allow vold_prepare_subdirs file_contexts_file:file r_file_perms;
-allow vold_prepare_subdirs self:global_capability_class_set { chown dac_override };
+allow vold_prepare_subdirs self:global_capability_class_set { chown dac_override fowner };
 allow vold_prepare_subdirs self:process setfscreate;
 allow vold_prepare_subdirs {
   system_data_file
   vendor_data_file
-}:dir { open read write add_name remove_name };
-allow vold_prepare_subdirs vold_data_file:dir { create open read write search getattr setattr remove_name rmdir };
+}:dir { open read write add_name remove_name relabelfrom };
+allow vold_prepare_subdirs system_data_file:file getattr;
+allow vold_prepare_subdirs vold_data_file:dir { create open read write search getattr setattr remove_name rmdir relabelto };
 allow vold_prepare_subdirs vold_data_file:file { getattr unlink };
-allow vold_prepare_subdirs storaged_data_file:dir create_dir_perms;
-allow vold_prepare_subdirs fingerprint_vendor_data_file:dir create_dir_perms;
+allow vold_prepare_subdirs storaged_data_file:dir { create_dir_perms relabelto };
+allow vold_prepare_subdirs storaged_data_file:file getattr;
+allow vold_prepare_subdirs fingerprint_vendor_data_file:dir { create_dir_perms relabelto };