fbdev: FB_OPENCORES should depend on HAS_DMA

If NO_DMA=y:

    drivers/built-in.o: In function `ocfb_remove':
    ocfb.c:(.text+0x27fee): undefined reference to `dma_free_coherent'
    drivers/built-in.o: In function `ocfb_probe':
    ocfb.c:(.text+0x28418): undefined reference to `dma_alloc_coherent'
    ocfb.c:(.text+0x284d2): undefined reference to `dma_free_coherent'
Signed-off-by: NGeert Uytterhoeven <geert@linux-m68k.org>
Acked-by: NStefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Signed-off-by: NTomi Valkeinen <tomi.valkeinen@ti.com>

drivers/video/Kconfig

@@ -982,7 +982,7 @@ config FB_PVR2
 
 config FB_OPENCORES
 	tristate "OpenCores VGA/LCD core 2.0 framebuffer support"
-	depends on FB
+	depends on FB && HAS_DMA
 	select FB_CFB_FILLRECT
 	select FB_CFB_COPYAREA
 	select FB_CFB_IMAGEBLIT