I wouldn't read too much into that. He refers to "the fundamental constituents of reality," which would include all types of particles. Electrons and quarks are only given as examples. If he meant to exclude bosons, he would have said so.
In the interview where he said this, he goes on to say:
And the very complex experience of the human or animal brain is somehow derived from the experience of the brain’s most basic parts.
Bosons, such as photons, are necessary for the physical function of the brain. Thus, if his premise is that consciousness of the brain is derived from the consciousness of its functional parts, he would have to include photons as functional parts and therefore having some simple consciousness.