Fix build on MIPS32

Remove stack handling function that's dead code that doesn't compile.

Task-number: QTBUG-58567
Change-Id: I704b0323522ce2a313d6cc85112f782872c3bf68
Reviewed-by: Lars Knoll <lars.knoll@qt.io>

src/3rdparty/masm/assembler/MacroAssembler.h

@@ -248,14 +248,6 @@ public:
     }
 #endif
     
-#if CPU(MIPS)
-    void poke(FPRegisterID src, int index = 0)
-    {
-        ASSERT(!(index & 1));
-        storeDouble(src, addressForPoke(index));
-    }
-#endif
-
     // Backwards banches, these are currently all implemented using existing forwards branch mechanisms.
     void branchPtr(RelationalCondition cond, RegisterID op1, TrustedImmPtr imm, Label target)
     {