[PATCH] firmware: qcom_scm: fix error for incompatible pointer

[Minwoo Im <minwoo.im.dev@gmail.com>]

The following error can happen when trying to build it:

```
drivers/firmware/qcom_scm.c: In function ‘qcom_scm_assign_mem’:
drivers/firmware/qcom_scm.c:460:47: error: passing argument 3 of ‘dma_alloc_coherent’ from incompatible pointer type [-Werror=incompatible-pointer-types]
  ptr = dma_alloc_coherent(__scm->dev, ptr_sz, &ptr_phys, GFP_KERNEL);
                                               ^
In file included from drivers/firmware/qcom_scm.c:12:0:
./include/linux/dma-mapping.h:636:21: note: expected ‘dma_addr_t * {aka long long unsigned int *}’ but argument is of type ‘phys_addr_t * {aka unsigned int *}’
 static inline void *dma_alloc_coherent(struct device *dev, size_t size,
                     ^~~~~~~~~~~~~~~~~~
```

We just can cast phys_addr_t to dma_addr_t here.

Cc: Andy Gross <agross@kernel.org>
Cc: David Brown <david.brown@linaro.org>
Signed-off-by: Minwoo Im <minwoo.im.dev@gmail.com>
---
 drivers/firmware/qcom_scm.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/firmware/qcom_scm.c b/drivers/firmware/qcom_scm.c
index 2ddc118dba1b..7f6c841fa200 100644
--- a/drivers/firmware/qcom_scm.c
+++ b/drivers/firmware/qcom_scm.c
@@ -457,7 +457,8 @@ int qcom_scm_assign_mem(phys_addr_t mem_addr, size_t mem_sz,
 	ptr_sz = ALIGN(src_sz, SZ_64) + ALIGN(mem_to_map_sz, SZ_64) +
 			ALIGN(dest_sz, SZ_64);
 
-	ptr = dma_alloc_coherent(__scm->dev, ptr_sz, &ptr_phys, GFP_KERNEL);
+	ptr = dma_alloc_coherent(__scm->dev, ptr_sz, (dma_addr_t *) &ptr_phys,
+					GFP_KERNEL);
 	if (!ptr)
 		return -ENOMEM;
 
-- 
2.17.1