[ARM] Add Neon saturating add and subtract instructions.

src/arm/assembler-arm.h

Index: src/arm/assembler-arm.h
diff --git a/src/arm/assembler-arm.h b/src/arm/assembler-arm.h
index d4f94029697905f6b91ae9ae728f19df380b4b6d..5e344d537984432e3ec50963998e01aae3763357 100644
--- a/src/arm/assembler-arm.h
+++ b/src/arm/assembler-arm.h
@@ -1374,9 +1374,13 @@ class Assembler : public AssemblerBase {
   void vadd(QwNeonRegister dst, QwNeonRegister src1, QwNeonRegister src2);
   void vadd(NeonSize size, QwNeonRegister dst, QwNeonRegister src1,
             QwNeonRegister src2);
+  void vqadd(NeonDataType dt, QwNeonRegister dst, QwNeonRegister src1,
+             QwNeonRegister src2);
   void vsub(QwNeonRegister dst, QwNeonRegister src1, QwNeonRegister src2);
   void vsub(NeonSize size, QwNeonRegister dst, QwNeonRegister src1,
             QwNeonRegister src2);
+  void vqsub(NeonDataType dt, QwNeonRegister dst, QwNeonRegister src1,
+             QwNeonRegister src2);
   void vmul(QwNeonRegister dst, QwNeonRegister src1,
             QwNeonRegister src2);
   void vmul(NeonSize size, QwNeonRegister dst, QwNeonRegister src1,