misc: strcpy be gone

Causes static analysis "vulnerability" warnings

Type: fix
Ticket: VPP-1837

Signed-off-by: Dave Barach <dave@barachs.net>
Change-Id: I272fa69251d70f62178e6dff0423c16f99937af1
diff --git a/src/vcl/ldp.c b/src/vcl/ldp.c
index 0dbc6a5..66c6d93 100644
--- a/src/vcl/ldp.c
+++ b/src/vcl/ldp.c
@@ -1814,8 +1814,8 @@
 		rv = -EFAULT;
 	      break;
 	    case TCP_CONGESTION:
-	      strcpy (optval, "cubic");
 	      *optlen = strlen ("cubic");
+	      strncpy (optval, "cubic", *optlen + 1);
 	      rv = 0;
 	      break;
 	    default: