MIPS: Added the stop() instruction with same behavior as on Arm simulator.

src/mips/macro-assembler-mips.h

Index: src/mips/macro-assembler-mips.h
diff --git a/src/mips/macro-assembler-mips.h b/src/mips/macro-assembler-mips.h
index bcb459ee04f3e69482c7fbffff98f39ce51b0e85..76447dc607b8b42e6a058539296ce705d02ef25a 100644
--- a/src/mips/macro-assembler-mips.h
+++ b/src/mips/macro-assembler-mips.h
@@ -459,9 +459,6 @@ DECLARE_NOTARGET_PROTOTYPE(Ret)
     li(dst, Operand(value), gen2instr);
   }
 
-  // Exception-generating instructions and debugging support.
-  void stop(const char* msg);
-
   // Push multiple registers on the stack.
   // Registers are saved in numerical order, with higher numbered registers
   // saved in higher memory addresses.