rpmsg: rename virtqueue_add_buf_gfp to virtqueue_add_buf

Since commit 7bb7aef2 "virtio: rename virtqueue_add_buf_gfp to virtqueue_add_buf",
virtqueue_add_buf_gfp is already rename to virtqueue_add_buf now.

This patch fixes below build error:
 CC [M]  drivers/rpmsg/virtio_rpmsg_bus.o
drivers/rpmsg/virtio_rpmsg_bus.c: In function 'rpmsg_send_offchannel_raw':
drivers/rpmsg/virtio_rpmsg_bus.c:723: error: implicit declaration of function 'virtqueue_add_buf_gfp'
make[2]: *** [drivers/rpmsg/virtio_rpmsg_bus.o] Error 1
make[1]: *** [drivers/rpmsg] Error 2
make: *** [drivers] Error 2

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Ohad Ben-Cohen <ohad@wizery.com>
diff --git a/drivers/rpmsg/virtio_rpmsg_bus.c b/drivers/rpmsg/virtio_rpmsg_bus.c
index 257683e..8980ac2 100644
--- a/drivers/rpmsg/virtio_rpmsg_bus.c
+++ b/drivers/rpmsg/virtio_rpmsg_bus.c
@@ -720,14 +720,14 @@
 	mutex_lock(&vrp->tx_lock);
 
 	/* add message to the remote processor's virtqueue */
-	err = virtqueue_add_buf_gfp(vrp->svq, &sg, 1, 0, msg, GFP_KERNEL);
+	err = virtqueue_add_buf(vrp->svq, &sg, 1, 0, msg, GFP_KERNEL);
 	if (err < 0) {
 		/*
 		 * need to reclaim the buffer here, otherwise it's lost
 		 * (memory won't leak, but rpmsg won't use it again for TX).
 		 * this will wait for a buffer management overhaul.
 		 */
-		dev_err(dev, "virtqueue_add_buf_gfp failed: %d\n", err);
+		dev_err(dev, "virtqueue_add_buf failed: %d\n", err);
 		goto out;
 	}
 
@@ -777,7 +777,7 @@
 	sg_init_one(&sg, msg, sizeof(*msg) + len);
 
 	/* add the buffer back to the remote processor's virtqueue */
-	err = virtqueue_add_buf_gfp(vrp->rvq, &sg, 0, 1, msg, GFP_KERNEL);
+	err = virtqueue_add_buf(vrp->rvq, &sg, 0, 1, msg, GFP_KERNEL);
 	if (err < 0) {
 		dev_err(dev, "failed to add a virtqueue buffer: %d\n", err);
 		return;
@@ -907,7 +907,7 @@
 
 		sg_init_one(&sg, cpu_addr, RPMSG_BUF_SIZE);
 
-		err = virtqueue_add_buf_gfp(vrp->rvq, &sg, 0, 1, cpu_addr,
+		err = virtqueue_add_buf(vrp->rvq, &sg, 0, 1, cpu_addr,
 								GFP_KERNEL);
 		WARN_ON(err < 0); /* sanity check; this can't really happen */
 	}