net: ll_temac: drop obsolete "NAMESIZE" define

... after commit "net/miiphy/serial: drop duplicate NAMESIZE
define" (sha1:f6add132) was applied. The building of the new
LL TEMAC network driver fails with error below:

xilinx_ll_temac.c: In function 'xilinx_ll_temac_initialize':
xilinx_ll_temac.c:301: error: 'NAMESIZE' undeclared (first use in this function)
xilinx_ll_temac.c:301: error: (Each undeclared identifier is reported only once
xilinx_ll_temac.c:301: error: for each function it appears in.)

Signed-off-by: Stephan Linz <linz@li-pro.net>
Acked-by: Mike Frysinger <vapier@gentoo.org>