Spelling fixes: lenght->length

Signed-off-by: Paulius Zaleckas <pauliusz@yahoo.com>
Signed-off-by: Adrian Bunk <bunk@kernel.org>
diff --git a/drivers/media/video/pwc/pwc-if.c b/drivers/media/video/pwc/pwc-if.c
index 7300ace..f991d72 100644
--- a/drivers/media/video/pwc/pwc-if.c
+++ b/drivers/media/video/pwc/pwc-if.c
@@ -542,7 +542,7 @@
 	}
 
 	if (pdev->read_frame != NULL) {
-		/* Decompression is a lenghty process, so it's outside of the lock.
+		/* Decompression is a lengthy process, so it's outside of the lock.
 		   This gives the isoc_handler the opportunity to fill more frames
 		   in the mean time.
 		*/