frame_relay: Fix error path on ioctl() failure

We don't want to pass -EINVAL as file descriptor into the bind() call.

Closes: CID#215529
Change-Id: Ic4d411c0ade6867c4fe2c01eb3368e6420158724
diff --git a/src/gb/gprs_ns2_fr.c b/src/gb/gprs_ns2_fr.c
index 80e3366..3315273 100644
--- a/src/gb/gprs_ns2_fr.c
+++ b/src/gb/gprs_ns2_fr.c
@@ -319,7 +319,7 @@
 			"cannot set this socket unblocking: %s\n",
 			strerror(errno));
 		close(fd);
-		fd = -EINVAL;
+		return -EINVAL;
 	}
 
 	rc = bind(fd, (struct sockaddr *)&addr, sizeof(addr));