[media] staging/media/go7007: Use kmemdup rather than duplicating its implementation

Found with coccicheck.
The semantic patch that makes this change is available
in scripts/coccinelle/api/memdup.cocci.

Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/staging/media/go7007/go7007-driver.c

@@ -108,14 +108,13 @@ static int go7007_load_encoder(struct go7007 *go)
 		return -1;
 	}
 	fw_len = fw_entry->size - 16;
-	bounce = kmalloc(fw_len, GFP_KERNEL);
+	bounce = kmemdup(fw_entry->data + 16, fw_len, GFP_KERNEL);
 	if (bounce == NULL) {
 		v4l2_err(go, "unable to allocate %d bytes for "
 				"firmware transfer\n", fw_len);
 		release_firmware(fw_entry);
 		return -1;
 	}
-	memcpy(bounce, fw_entry->data + 16, fw_len);
 	release_firmware(fw_entry);
 	if (go7007_interface_reset(go) < 0 ||
 			go7007_send_firmware(go, bounce, fw_len) < 0 ||