PPC/s390: [wasm] Turn ValueType from an enum to a class

Port f3b4167f

Original Commit Message:

    In preparation for adding reference types, which need an additional
    parameter to indicate the referenced type.

R=jkummerow@chromium.org, joransiu@ca.ibm.com, jyan@ca.ibm.com, michael_dawson@ca.ibm.com
BUG=
LOG=N

Change-Id: Ia6d933611440096247dda159846f6c119f5167d5
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2101607Reviewed-by: Junliang Yan <jyan@ca.ibm.com>
Commit-Queue: Milad Farazmand <miladfar@ca.ibm.com>
Cr-Commit-Position: refs/heads/master@{#66689}

src/wasm/baseline/ppc/liftoff-assembler-ppc.h

@@ -66,17 +66,17 @@ constexpr int LiftoffAssembler::StaticStackFrameSize() {
 }
 
 int LiftoffAssembler::SlotSizeForType(ValueType type) {
-  switch (type) {
-    case kWasmS128:
-      return ValueTypes::ElementSizeInBytes(type);
+  switch (type.kind()) {
+    case ValueType::kS128:
+      return type.element_size_bytes();
     default:
       return kStackSlotSize;
   }
 }
 
 bool LiftoffAssembler::NeedsAlignment(ValueType type) {
-  switch (type) {
-    case kWasmS128:
+  switch (type.kind()) {
+    case ValueType::kS128:
       return true;
     default:
       // No alignment because all other types are kStackSlotSize.

src/wasm/baseline/s390/liftoff-assembler-s390.h

@@ -65,17 +65,17 @@ constexpr int LiftoffAssembler::StaticStackFrameSize() {
 }
 
 int LiftoffAssembler::SlotSizeForType(ValueType type) {
-  switch (type) {
-    case kWasmS128:
-      return ValueTypes::ElementSizeInBytes(type);
+  switch (type.kind()) {
+    case ValueType::kS128:
+      return type.element_size_bytes();
     default:
       return kStackSlotSize;
   }
 }
 
 bool LiftoffAssembler::NeedsAlignment(ValueType type) {
-  switch (type) {
-    case kWasmS128:
+  switch (type.kind()) {
+    case ValueType::kS128:
       return true;
     default:
       // No alignment because all other types are kStackSlotSize.