The name also sounds like oriole, as in the birds. The connection of Orell to birds has a variety of connection points. But, as mentioned, there is no confirmation from GRRM.
Without a confirmation from GRRM, it's possible that the name comes from the Orrell surname and the eagle part is a coincidence.
This unusual name is of early Medieval English origin, and is a
locational surname deriving from either of the places called "Orrell"
in Lancashire, one of which is situated in the parish of Wigan, and
the other in the parish of Sefton. Both places share the same meaning
and derivation, which is from the Old English pre 7th Century word
"ora", ore, and "hyll", hill;
I think it's best to avoid assumption and admire the synchronicity.