Flush instruction cache in NativeModule::Link

Tests are failing on MIPS with bus error because instruction cache is not flushed.

Change-Id: I1725a87ea2dc36ffde767d10a0c4deea0e069c09
Reviewed-on: https://chromium-review.googlesource.com/950722Reviewed-by: Andreas Haas <ahaas@chromium.org>
Commit-Queue: Ivica Bogosavljevic <ivica.bogosavljevic@mips.com>
Cr-Commit-Position: refs/heads/master@{#51768}

src/wasm/wasm-code-manager.cc

@@ -562,6 +562,8 @@ void NativeModule::Link(uint32_t index) {
     it.rinfo()->set_wasm_call_address(target_addr,
                                       ICacheFlushMode::SKIP_ICACHE_FLUSH);
   }
+  Assembler::FlushICache(code->instructions().start(),
+                         code->instructions().size());
 }
 
 Address NativeModule::AllocateForCode(size_t size) {