drivers/net: fix broadcom/bcmsysport.c compile fail on SPARC

To fix:

  CC      drivers/net/ethernet/broadcom/bcmsysport.o
In file included from drivers/net/ethernet/broadcom/bcmsysport.c:28:0:
drivers/net/ethernet/broadcom/bcmsysport.h:41:8: error: redefinition of 'struct tsb'
arch/sparc/include/asm/mmu_64.h:65:8: note: originally defined here
make[1]: *** [drivers/net/ethernet/broadcom/bcmsysport.o] Error 1

we change struct tsb to struct bcm_tsb in the broadcom driver in
order to avoid the namespace collision.  For consistency, we also
change struct rsb to struct bcm_rsb, so the Rx/Tx symmetry is
maintained.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>