nds32: drop bi_enetaddr from global data

Nothing is using this, so punt it from the gd.  Seems to just be a copy
& paste wart from the initial port.
Signed-off-by: NMike Frysinger <vapier@gentoo.org>

arch/nds32/include/asm/u-boot.h

@@ -40,7 +40,6 @@
 
 typedef struct bd_info {
 	int		bi_baudrate;	/* serial console baudrate */
-	unsigned char	bi_enetaddr[6]; /* Ethernet adress */
 	unsigned long	bi_arch_number;	/* unique id for this board */
 	unsigned long	bi_boot_params;	/* where this board expects params */
 	unsigned long	bi_memstart;	/* start of DRAM memory */