net: ll_temac: Remove sparse warnings

Remove sparse warnings:
drivers/net/ethernet/xilinx/ll_temac_main.c:65:16: warning: cast removes
address space of expression
drivers/net/ethernet/xilinx/ll_temac_main.c:70:9: warning: cast removes
address space of expression
drivers/net/ethernet/xilinx/ll_temac_main.c:127:16: warning: cast
removes address space of expression
drivers/net/ethernet/xilinx/ll_temac_main.c:137:9: warning: cast removes
address space of expression
drivers/net/ethernet/xilinx/ll_temac_main.c:409:3: warning: symbol
'temac_options' was not declared. Should it be static?
drivers/net/ethernet/xilinx/ll_temac_main.c:590:6: warning: symbol
'temac_adjust_link' was not declared. Should it be static?

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: David S. Miller <davem@davemloft.net>