BugLink: https://bugs.launchpad.net/bugs/1775771

[ Upstream commit 55496d3f ]

The generic DMA API uses dev->dma_mask to check the DMA addressable
memory bitmask, and warns if no mask is set or even allocated.

Set z->dev.dma_coherent_mask on Zorro bus scan, and make z->dev.dma_mask
to point to z->dev.dma_coherent_mask so device drivers that need DMA have
everything set up to avoid warnings from dma_alloc_coherent(). Drivers can
still use dma_set_mask_and_coherent() to explicitly set their DMA bit mask.
Signed-off-by: Michael Schmitz <schmitzmic@gmail.com>
[geert: Handle Zorro II with 24-bit address space]
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Juerg Haefliger <juergh@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>