dma: fix comments

Correct spelling typo in drivers/dma.

Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c
index e4feba6..2343d7d 100644
--- a/drivers/dma/pl330.c
+++ b/drivers/dma/pl330.c
@@ -522,7 +522,7 @@
 	/* In the DMAC pool */
 	FREE,
 	/*
-	 * Allocted to some channel during prep_xxx
+	 * Allocated to some channel during prep_xxx
 	 * Also may be sitting on the work_list.
 	 */
 	PREP,