common: mii: Do not allow to exceed max phy limit

Phy can have addresses 0-31. Check this boundary to ensure that user
can't call commands on phy address 32 and more.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
1 file changed