Give vold setattr/getattr permissions to foreign dex files domain.

Vold needs to be able to query if the directory exists and
eventually to fix permissions and the owner.

Typical error:
W vold    : type=1400 audit(0.0:485): avc: denied { getattr } 
for path="/data/misc/profiles/cur/11/foreign-dex" dev="dm-2" 
ino=343857 scontext=u:r:vold:s0
tcontext=u:object_r:user_profile_foreign_dex_data_file:s0 tclass=dir 
permissive=0


Bug: 27517932
Change-Id: Iff10c864634baa97cc814916ee7495b262e0c7eb