async_tx: fix compile breakage, mark do_async_xor __always_inline

From: Dan Williams <dan.j.williams@intel.com>

do_async_xor must be compiled away on !HAS_DMA archs.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---

 crypto/async_tx/async_xor.c |    6 +++++-
 1 files changed, 5 insertions(+), 1 deletions(-)


diff --git a/crypto/async_tx/async_xor.c b/crypto/async_tx/async_xor.c
index 2575f67..716885a 100644
--- a/crypto/async_tx/async_xor.c
+++ b/crypto/async_tx/async_xor.c
@@ -30,7 +30,11 @@
 #include <linux/raid/xor.h>
 #include <linux/async_tx.h>
 
-static void
+/* do_async_xor - dma map the pages and perform the xor with an engine.
+ * 	This routine is marked __always_inline so it can be compiled away
+ * 	when CONFIG_DMA_ENGINE=n
+ */
+static __always_inline void
 do_async_xor(struct dma_async_tx_descriptor *tx, struct dma_device *device,
 	struct dma_chan *chan, struct page *dest, struct page **src_list,
 	unsigned int offset, unsigned int src_cnt, size_t len,