vold_prepare_subdirs: grant chown

Addresses:
avc: denied { chown } for comm="vold_prepare_su" capability=0
scontext=u:r:vold_prepare_subdirs:s0
tcontext=u:r:vold_prepare_subdirs:s0 tclass=capability

Bug: 71796118
Test: build
Change-Id: I64b2f1ad8d6e0748c5820b8a37a4fc4f4101d1fb

private/vold_prepare_subdirs.te

@@ -7,7 +7,7 @@ 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 dac_override;
+allow vold_prepare_subdirs self:global_capability_class_set { chown dac_override };
 allow vold_prepare_subdirs self:process setfscreate;
 allow vold_prepare_subdirs system_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 };