Only run dependency extractors on files with attached attributes

Only run dependency extractors on files with attached attributes
- looking at file colors still works as every relevant type has
  RPMFC_INCLUDE set but this includes various things we might not have
  attributes for, just avoids unnecessary work and is more obvious this way
- should really have been in commit ad2c8485ea109d37a2fb8ee9ed5f688eef282bf8