device.h: dma_mem is only needed for HAVE_GENERIC_DMA_COHERENT

No need to carry an unused field around.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Christoph Hellwig 2018-12-25 14:03:32 +01:00
commit 2b28129613