ide: icside.c: Fix compile with CONFIG_BLK_DEV_IDEDMA_ICS=n

The icside driver can be configured without DMA support, but it
doesn't compile then, because DMA operations are referenced.

drivers/ide/icside.c:523: error: 'icside_v6_port_ops' undeclared
drivers/ide/icside.c:522: error: 'icside_dma_init' undeclared

Signed-off-by: Christian <Dietrich&lt;christian.dietrich@informatik.uni-erlangen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>