make ar5416Addac_9160 and ar5416Addac_9160 const
make ar5416Addac_9160 and ar5416Addac_9160 const

These were not const, I guess we skipped them. Will send
a respective upstream patch.

Signed-off-by: Luis R. Rodriguez <79e6b8107a8aa3944e09fad43634662ac3b91a0b@atheros.com>

qca/qca-swiss-army-knife,mcgrof/qca-swiss-army-knife,qca/qca-swiss-army-knife,qca/qca-swiss-army-knife,qca/qca-swiss-army-knife