net: tsec: Use tsec_private pointer as the parameter for internal routines

For internal routines like redundant_init(), startup_tsec() and
init_phy(), change to use tsec_private pointer as the parameter.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Acked-by: Joe Hershberger <joe.hershberger@ni.com>