net: via: VIA_RHINE and VIA_VELOCITY should depend on HAS_DMA

If NO_DMA=y:

    ERROR: "dma_sync_single_for_cpu" [drivers/net/ethernet/via/via-rhine.ko] undefined!
    ERROR: "dma_set_mask" [drivers/net/ethernet/via/via-rhine.ko] undefined!
    ERROR: "dma_mapping_error" [drivers/net/ethernet/via/via-rhine.ko] undefined!
    ERROR: "dma_map_single" [drivers/net/ethernet/via/via-rhine.ko] undefined!
    ERROR: "dma_alloc_coherent" [drivers/net/ethernet/via/via-rhine.ko] undefined!
    ERROR: "dma_free_coherent" [drivers/net/ethernet/via/via-rhine.ko] undefined!
    ERROR: "dma_unmap_single" [drivers/net/ethernet/via/via-rhine.ko] undefined!
    ERROR: "dma_map_page" [drivers/net/ethernet/via/via-velocity.ko] undefined!
    ERROR: "dma_sync_single_for_cpu" [drivers/net/ethernet/via/via-velocity.ko] undefined!
    ERROR: "dma_free_coherent" [drivers/net/ethernet/via/via-velocity.ko] undefined!
    ERROR: "dma_unmap_single" [drivers/net/ethernet/via/via-velocity.ko] undefined!
    ERROR: "dma_map_single" [drivers/net/ethernet/via/via-velocity.ko] undefined!
    ERROR: "dma_alloc_coherent" [drivers/net/ethernet/via/via-velocity.ko] undefined!

Before, the symbols depended implicitly on HAS_DMA through PCI or
USE_OF.  Add explicit dependencies on HAS_DMA to fix this.

Fixes: b7d3282a

 ("net: via/Kconfig: replace USE_OF with OF_???")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: David S. Miller <davem@davemloft.net>