dbri: Fix compiler warning

dbri uses 'u32' for dma handle while invoking kernel DMA APIs,
instead of using dma_addr_t. This hasn't caused any 'incompatible
pointer type' warning on SPARC because until now dma_addr_t is of
type u32. However, recent changes in SPARC ATU (iommu) enabled 64bit
DMA and therefore dma_addr_t became of type u64. This makes
'incompatible pointer type' warnings inevitable.

e.g.
sound/sparc/dbri.c: In function ‘snd_dbri_create’:
sound/sparc/dbri.c:2538: warning: passing argument 3 of ‘dma_zalloc_coherent’ from incompatible pointer type
./include/linux/dma-mapping.h:608: note: expected ‘dma_addr_t *’ but argument is of type ‘u32 *’

For the record, dbri(sbus) driver never executes on sun4v. Therefore
even though 64bit DMA is enabled on SPARC, dbri continues to use
legacy iommu that guarantees DMA address is always in 32bit range.

This patch resolves above compiler warning.

Signed-off-by: Tushar Dave <tushar.n.dave@oracle.com>
Reviewed-by: thomas tai <thomas.tai@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>