MIPS64: Fix `[wasm] Merge the WasmContext into WasmInstanceObject`

Fix a6d974fe

Change-Id: I0c8c5f3e86fcb4954f8854d7068c5267abb748a4
Reviewed-on: https://chromium-review.googlesource.com/1004580Reviewed-by: Sreten Kovacevic <sreten.kovacevic@mips.com>
Commit-Queue: Ivica Bogosavljevic <ivica.bogosavljevic@mips.com>
Cr-Commit-Position: refs/heads/master@{#52512}

src/builtins/mips64/builtins-mips64.cc

@@ -2629,7 +2629,7 @@ void Builtins::Generate_WasmCompileLazy(MacroAssembler* masm) {
     __ MultiPop(gp_regs);
   }
   // Finally, jump to the entrypoint.
-  __ Jump(at);
+  __ Jump(v0);
 }
 
 #undef __