staging: gasket: page table: use GFP_KERNEL for dma_alloc_coherent

Flags should be specified for dma_alloc_coherent() call.  Use
GFP_KERNEL, it's fine to sleep here.
Signed-off-by: Todd Poynor <toddpoynor@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/gasket/gasket_page_table.c

@@ -1287,7 +1287,7 @@ int gasket_alloc_coherent_memory(struct gasket_dev *gasket_dev, u64 size,
 		return -EINVAL;
 
 	mem = dma_alloc_coherent(gasket_get_device(gasket_dev),
-				 num_pages * PAGE_SIZE, &handle, 0);
+				 num_pages * PAGE_SIZE, &handle, GFP_KERNEL);
 	if (!mem)
 		goto nomem;