lightnvm: pblk: fix NULL check before some freeing functions is not needed

fixed the below warning:
./drivers/lightnvm/pblk-gc.c:27:2-7: WARNING: NULL check before some
freeing functions is not needed.

Signed-off-by: Tian Tao <tiantao6@hisilicon.com>
---
 drivers/lightnvm/pblk-gc.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/lightnvm/pblk-gc.c b/drivers/lightnvm/pblk-gc.c
index 2581eeb..b31658b 100644
--- a/drivers/lightnvm/pblk-gc.c
+++ b/drivers/lightnvm/pblk-gc.c

@@ -23,8 +23,7 @@
 
 static void pblk_gc_free_gc_rq(struct pblk_gc_rq *gc_rq)
 {
-	if (gc_rq->data)
-		vfree(gc_rq->data);
+	vfree(gc_rq->data);
 	kfree(gc_rq);
 }
 

-- 
2.7.4