net: dsa: sja1105: Make 'sja1105et_regs' and 'sja1105pqrs_regs' static

drivers/net/dsa/sja1105/sja1105_spi.c:486:21: warning: symbol 'sja1105et_regs' was not declared. Should it be static?
drivers/net/dsa/sja1105/sja1105_spi.c:511:21: warning: symbol 'sja1105pqrs_regs' was not declared. Should it be static?

Fixes: 8aa9ebcc ("net: dsa: Introduce driver for NXP SJA1105 5-port L2 switch")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wang Hai <wanghai26@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>