Bug 1687417 - MIPS32 nojit, silence an assert and define a couple stubs. r=yury

A static_assert is failing but this is not relevant for nojit builds,
so silence it.

Two stub functions need to be defined for compilation to succeed,
but they need to be ifdeffed carefully to avoid unused-function
errors on CI.

Differential Revision: https://phabricator.services.mozilla.com/D125526

js/src/wasm/WasmBCMemory.cpp

@@ -728,7 +728,7 @@ static void Deallocate(BaseCompiler* bc, RegI64 temp) {
   bc->freeI32(bc->specific_.ecx);
 }
 
-#elif defined(__wasi__)
+#elif defined(__wasi__) || (defined(JS_CODEGEN_NONE) && !defined(JS_64BIT))
 
 static void Allocate(BaseCompiler*, RegI64*, RegI64*) {}
 static void Deallocate(BaseCompiler*, RegI64) {}

js/src/wasm/WasmDebugFrame.cpp

@@ -47,8 +47,10 @@ void DebugFrame::alignmentStaticAsserts() {
 
   static_assert(WasmStackAlignment >= Alignment,
                 "Aligned by ABI before pushing DebugFrame");
+#ifndef JS_CODEGEN_NONE
   static_assert((offsetof(DebugFrame, frame_) + sizeof(Frame)) % Alignment == 0,
                 "Aligned after pushing DebugFrame");
+#endif
 #ifdef JS_CODEGEN_ARM64
   // This constraint may or may not be necessary.  If you hit this because
   // you've changed the frame size then feel free to remove it, but be extra