gck: Add some precondition checks to gck_attributes_find_xxxx()
gck: Add some precondition checks to gck_attributes_find_xxxx()

Distrotech/gcr,stefwalter/gcr,stefwalter/gcr,Distrotech/gcr,stefwalter/gcr,Distrotech/gcr,stefwalter/gcr,Distrotech/gcr