JIT: Fix inconsistent handling of sub-word instance git/put

The portable interpreter and fast interpreter use 32-bit accesses
for all sub-word scalars.  The JIT generated code to tailor the access
to the data size.  It doesn't matter which approach is taken, but all
interpreters & JIT must be consistent.  Changing the JIT to use 32-bit
accesses for all sub-word instance scalars.

Fix for Issue 2973137

Change-Id: I8b1e9e6be075012c7c174728b77c7a76884975b7
diff --git a/vm/compiler/codegen/arm/CodegenDriver.c b/vm/compiler/codegen/arm/CodegenDriver.c
index a04371e..0b6e433 100644
--- a/vm/compiler/codegen/arm/CodegenDriver.c
+++ b/vm/compiler/codegen/arm/CodegenDriver.c
@@ -2328,24 +2328,20 @@
             // NOTE: intentional fallthrough
         case OP_IGET:
         case OP_IGET_OBJECT:
-            genIGet(cUnit, mir, kWord, fieldOffset, isVolatile);
-            break;
         case OP_IGET_BOOLEAN:
-            genIGet(cUnit, mir, kUnsignedByte, fieldOffset, isVolatile);
-            break;
         case OP_IGET_BYTE:
-            genIGet(cUnit, mir, kSignedByte, fieldOffset, isVolatile);
-            break;
         case OP_IGET_CHAR:
-            genIGet(cUnit, mir, kUnsignedHalf, fieldOffset, isVolatile);
-            break;
         case OP_IGET_SHORT:
-            genIGet(cUnit, mir, kSignedHalf, fieldOffset, isVolatile);
+            genIGet(cUnit, mir, kWord, fieldOffset, isVolatile);
             break;
         case OP_IPUT_WIDE:
             genIPutWide(cUnit, mir, fieldOffset);
             break;
         case OP_IPUT:
+        case OP_IPUT_SHORT:
+        case OP_IPUT_CHAR:
+        case OP_IPUT_BYTE:
+        case OP_IPUT_BOOLEAN:
             genIPut(cUnit, mir, kWord, fieldOffset, false, isVolatile);
             break;
         case OP_IPUT_VOLATILE:
@@ -2355,16 +2351,6 @@
         case OP_IPUT_OBJECT:
             genIPut(cUnit, mir, kWord, fieldOffset, true, isVolatile);
             break;
-        case OP_IPUT_SHORT:
-        case OP_IPUT_CHAR:
-            genIPut(cUnit, mir, kUnsignedHalf, fieldOffset, false, isVolatile);
-            break;
-        case OP_IPUT_BYTE:
-            genIPut(cUnit, mir, kSignedByte, fieldOffset, false, isVolatile);
-            break;
-        case OP_IPUT_BOOLEAN:
-            genIPut(cUnit, mir, kUnsignedByte, fieldOffset, false, isVolatile);
-            break;
         case OP_IGET_WIDE_VOLATILE:
         case OP_IPUT_WIDE_VOLATILE:
             genInterpSingleStep(cUnit, mir);