drivers: staging: android: ion: Kconfig: Let it also depend on HAS_DMA

ION need HAS_DMA (e.g. need DMA_SHARED_BUFFER), so it has to depend on HAS_DMA, or can not pass compiling with allmodconfig under score which NO_DMA. And the related error:

CC drivers/staging/android/ion/ion_cma_heap.o
drivers/staging/android/ion/ion_cma_heap.c: In function 'ion_cma_mmap':
drivers/staging/android/ion/ion_cma_heap.c:168:2: error: implicit declaration of function 'dma_mmap_coherent' [-Werror=implicit-function-declaration]

    return dma_mmap_coherent(dev, vma, info->cpu_addr, info->handle,
    ^

cc1: some warnings being treated as errors
make[4]: *** [drivers/staging/android/ion/ion_cma_heap.o] Error 1 make[3]: *** [drivers/staging/android/ion] Error 2 make[2]: *** [drivers/staging/android] Error 2 make[1]: *** [drivers/staging] Error 2
make: *** [drivers] Error 2

Signed-off-by Chen Gang <[email protected]>

---
 drivers/staging/android/ion/Kconfig | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

drivers/staging/android/ion/Kconfig +1 -2

index 0f8fec1..0a6e4d0 100644
@@ -1,6 +1,6 @@
 menuconfig ION
        bool "Ion Memory Manager"
-       depends on HAVE_MEMBLOCK
+       depends on HAVE_MEMBLOCK && HAS_DMA
        select GENERIC_ALLOCATOR
        select DMA_SHARED_BUFFER
        ---help---
--

1.9.2.459.g68773ac