[WebAssembly] Update type checker message in notypecheck.s

This was missing from llvm#110094.

Author: aheejin

clang/test/Driver/notypecheck.s

@@ -5,7 +5,7 @@
 
 # Verify that without -Wa,--no-type-check the assembler will error out
 # RUN: not %clang %s -c -o tmp.o -target wasm32-unknown-unknown 2>&1 | FileCheck --check-prefix=ERROR %s
-# ERROR: error: popped i64, expected i32
+# ERROR: error: type mismatch, expected [i32] but got [i64]
 
 foo:
   .functype  foo () -> (i32)