WebAssembly: add missing expected failures exposed by r256890

llvm-svn: 256948
diff --git a/llvm/lib/Target/WebAssembly/known_gcc_test_failures.txt b/llvm/lib/Target/WebAssembly/known_gcc_test_failures.txt
index 92ecde3..f9a0ea6 100644
--- a/llvm/lib/Target/WebAssembly/known_gcc_test_failures.txt
+++ b/llvm/lib/Target/WebAssembly/known_gcc_test_failures.txt
@@ -10,6 +10,7 @@
 20030916-1.c
 20031012-1.c
 20041126-1.c
+20050502-2.c
 20060420-1.c
 20071202-1.c
 20120808-1.c