fbdev: FB_GOLDFISH should depend on HAS_DMA

If NO_DMA=y:

  drivers/built-in.o: In function `goldfish_fb_remove':
  drivers/video/goldfishfb.c:301: undefined reference to `dma_free_coherent'
  drivers/built-in.o: In function `goldfish_fb_probe':
  drivers/video/goldfishfb.c:247: undefined reference to `dma_alloc_coherent'
  drivers/video/goldfishfb.c:280: undefined reference to `dma_free_coherent'

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>