staging: et131x: Fix et131x sparse warnings

This fixes the following warnings:

et1310_mac.c:375:44: warning: incorrect type in initializer (different address spaces)
et1310_mac.c:382:28: warning: incorrect type in argument 2 (different address spaces)
et1310_mac.c:384:31: warning: incorrect type in argument 2 (different address spaces)
et131x_initpci.c:555:5: warning: symbol 'et131x_mii_probe' was not declared. Should it be static?
et131x_netdev.c:267:5: warning: symbol 'et131x_ioctl' was not declared. Should it be static?
et131x_netdev.c:285:5: warning: symbol 'et131x_set_packet_filter' was not declared. Should it be static?
et131x_netdev.c:347:6: warning: symbol 'et131x_multicast' was not declared. Should it be static?
et131x_netdev.c:420:5: warning: symbol 'et131x_tx' was not declared. Should it be static?
et131x_netdev.c:453:6: warning: symbol 'et131x_tx_timeout' was not declared. Should it be static?
et131x_netdev.c:511:5: warning: symbol 'et131x_change_mtu' was not declared. Should it be static?
et131x_netdev.c:564:5: warning: symbol 'et131x_set_mac_addr' was not declared. Should it be static?

Signed-off-by: Mark Einon <mark.einon@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>