net: ag7xxx: Comment register names

The register constants don't use the exact names that are used in the
TRM, so add comments that use the exact names so that it is clear what
register is being referred to.

https://www.atheros-drivers.com/qualcomm-atheros-datasheets-for-AR9331.html

Signed-off-by: Joe Hershberger <joe.hershberger@ni.com>
Acked-by: Marek Vasut <marex@denx.de>
1 file changed