BUG_ON conversion for drivers/media/video/pwc/pwc-if.c

This patch converts a if () BUG(); construct to BUG_ON();
which occupies less space, uses unlikely and is safer when
BUG() is disabled.

Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
diff --git a/drivers/media/video/pwc/pwc-if.c b/drivers/media/video/pwc/pwc-if.c
index 46c1148..e8db6e5 100644
--- a/drivers/media/video/pwc/pwc-if.c
+++ b/drivers/media/video/pwc/pwc-if.c
@@ -1095,8 +1095,7 @@
 	PWC_DEBUG_OPEN(">> video_open called(vdev = 0x%p).\n", vdev);
 
 	pdev = (struct pwc_device *)vdev->priv;
-	if (pdev == NULL)
-		BUG();
+	BUG_ON(!pdev);
 	if (pdev->vopen) {
 		PWC_DEBUG_OPEN("I'm busy, someone is using the device.\n");
 		return -EBUSY;