Merge branch 'fs_enet-opt'

Christophe Leroy says:

====================
Optimisation of fs_enet ethernet driver

This set optimises the freescale fs_enet ethernet driver:
1/ Merge of RX and TX NAPI functions in order to limit the amount of
interrupts
2/ Do not unmap DMA when packets len is below copybreak, otherwise there
is no benefit in copying the skb instead of allocating a new one
3/ Make copybreak value configurable as the optimised value is not the
same on all targets
====================

Signed-off-by: David S. Miller <davem@davemloft.net>