wimax: fix i2400m printk formats

Fix printk format warnings:

drivers/net/wimax/i2400m/netdev.c:523: warning: format '%zu' expects type 'size_t', but argument 7 has type 'unsigned int'
drivers/net/wimax/i2400m/netdev.c:548: warning: format '%zu' expects type 'size_t', but argument 7 has type 'unsigned int'

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Inaky Perez-Gonzalez <inaky@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>