drivers/dma/iop-adma: Use dma_alloc_writecombine() kernel-style

dma_alloc_writecombine()'s call and return value check is
tangled in all in one call. Untangle both calls according to
kernel coding style.
Signed-off-by: Luis R. Rodriguez <mcgrof@suse.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: airlied@linux.ie
Cc: benh@kernel.crashing.org
Cc: bhelgaas@google.com
Cc: daniel.vetter@ffwll.ch
Cc: dmaengine@vger.kernel.org
Cc: konrad.wilk@oracle.com
Cc: luto@amacapital.net
Cc: mst@redhat.com
Cc: tomi.valkeinen@ti.com
Cc: toshi.kani@hp.com
Cc: xen-devel@lists.xensource.com
Link: http://lkml.kernel.org/r/1440443613-13696-10-git-send-email-mcgrof@do-not-panic.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

drivers/dma/iop-adma.c

@@ -1300,10 +1300,11 @@ static int iop_adma_probe(struct platform_device *pdev)
 	 * note: writecombine gives slightly better performance, but
 	 * requires that we explicitly flush the writes
 	 */
-	if ((adev->dma_desc_pool_virt = dma_alloc_writecombine(&pdev->dev,
-					plat_data->pool_size,
-					&adev->dma_desc_pool,
-					GFP_KERNEL)) == NULL) {
+	adev->dma_desc_pool_virt = dma_alloc_writecombine(&pdev->dev,
+							  plat_data->pool_size,
+							  &adev->dma_desc_pool,
+							  GFP_KERNEL);
+	if (!adev->dma_desc_pool_virt) {
 		ret = -ENOMEM;
 		goto err_free_adev;
 	}