S390: rename memory offset during vector load and store

Change-Id: I586f3331fc8f468f799915e02e5863310e98937c
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2636843Reviewed-by: Junliang Yan <junyan@redhat.com>
Commit-Queue: Milad Fa <mfarazma@redhat.com>
Cr-Commit-Position: refs/heads/master@{#72176}

src/compiler/backend/s390/code-generator-s390.cc

@@ -2318,7 +2318,7 @@ CodeGenerator::CodeGenResult CodeGenerator::AssembleArchInstruction(
       } else {
         __ lrvg(r0, operand);
         __ lrvg(r1, MemOperand(operand.rx(), operand.rb(),
-                               operand.offset() + kBitsPerByte));
+                               operand.offset() + kSystemPointerSize));
         __ vlvgp(i.OutputSimd128Register(), r1, r0);
       }
       break;
@@ -2385,7 +2385,7 @@ CodeGenerator::CodeGenResult CodeGenerator::AssembleArchInstruction(
                 Condition(3));
         __ strvg(r0, operand);
         __ strvg(r1, MemOperand(operand.rx(), operand.rb(),
-                                operand.offset() + kBitsPerByte));
+                                operand.offset() + kSystemPointerSize));
       }
       break;
     }