Another clarifying rename and a bit more automation.

kNumDalvikInstructions is now kNumPackedOpcodes, there is a new
kMaxOpcodeValue, and both are generated by opcode-gen.

Change-Id: Ic46f1f52d2d21382452c8e777024f4a985ad31d3
Bonus: Reworded the switch and array data comment for clarity.
diff --git a/vm/compiler/codegen/arm/CodegenCommon.c b/vm/compiler/codegen/arm/CodegenCommon.c
index 05cead3..4a20579 100644
--- a/vm/compiler/codegen/arm/CodegenCommon.c
+++ b/vm/compiler/codegen/arm/CodegenCommon.c
@@ -30,7 +30,7 @@
 static intptr_t templateEntryOffsets[TEMPLATE_LAST_MARK];
 
 /* Track exercised opcodes */
-static int opcodeCoverage[kNumDalvikInstructions];
+static int opcodeCoverage[kNumPackedOpcodes];
 
 static void setMemRefType(ArmLIR *lir, bool isLoad, int memType)
 {