csync oC Util: set field flag correctly to avoid etag memleak.

The fields varialbe should contain or'ed flags of the fields set
in the csync_vio_file_stat_t struct. The problem was that the field
for CSYNC_VIO_FILE_STAT_FIELDS_PERM was assigned rather than or'ed
which makes the release function for the struct not freeing the
etag memory => memleak.