net: phy: broadcom: Move bcm54xx_auxctl_{read, write} to common library

We are going to need these functions to implement support for Broadcom
Wirespeed, aka downshift.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
3 files changed