Altera TSE: Add missing include to silence sparse warnings

This fixes the following sparse warnings:

drivers/net/ethernet/altera/altera_msgdma.c:23:5: warning: symbol 'msgdma_initialize' was not declared. Should it be static?
drivers/net/ethernet/altera/altera_msgdma.c:28:6: warning: symbol 'msgdma_uninitialize' was not declared. Should it be static?
drivers/net/ethernet/altera/altera_msgdma.c:32:6: warning: symbol 'msgdma_reset' was not declared. Should it be static?
drivers/net/ethernet/altera/altera_msgdma.c:77:6: warning: symbol 'msgdma_disable_rxirq' was not declared. Should it be static?
drivers/net/ethernet/altera/altera_msgdma.c:83:6: warning: symbol 'msgdma_enable_rxirq' was not declared. Should it be static?
drivers/net/ethernet/altera/altera_msgdma.c:89:6: warning: symbol 'msgdma_disable_txirq' was not declared. Should it be static?
drivers/net/ethernet/altera/altera_msgdma.c:95:6: warning: symbol 'msgdma_enable_txirq' was not declared. Should it be static?
drivers/net/ethernet/altera/altera_msgdma.c:101:6: warning: symbol 'msgdma_clear_rxirq' was not declared. Should it be static?
drivers/net/ethernet/altera/altera_msgdma.c:107:6: warning: symbol 'msgdma_clear_txirq' was not declared. Should it be static?
drivers/net/ethernet/altera/altera_msgdma.c:114:5: warning: symbol 'msgdma_tx_buffer' was not declared. Should it be static?
drivers/net/ethernet/altera/altera_msgdma.c:129:5: warning: symbol 'msgdma_tx_completions' was not declared. Should it be static?
drivers/net/ethernet/altera/altera_msgdma.c:154:5: warning: symbol 'msgdma_add_rx_desc' was not declared. Should it be static?
drivers/net/ethernet/altera/altera_msgdma.c:181:5: warning: symbol 'msgdma_rx_status' was not declared. Should it be static?

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Acked-by: Vince Bridgers <vbridgers2013@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>