net: ethernet: cpsw: fix build warnings for CPSW when CPTS not selected

net: ethernet: cpsw: fix build warnings for CPSW when CPTS not selected

CC      drivers/net/ethernet/ti/cpsw.o
drivers/net/ethernet/ti/cpsw.c: In function 'cpsw_ndo_ioctl':
drivers/net/ethernet/ti/cpsw.c:881:20: warning: unused variable 'priv'

The build warning is generated when CPTS is not selected in Kernel Build.
Fixing by passing the net_device pointer to cpts IOCTL instead of passing priv

Signed-off-by: Mugunthan V N <mugunthanvnm@ti.com>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>