Refactored validation_state, added new types

- validation_state.cpp uses functions from opcode.h instead of in-place
switches which need to be updated.
- added new spirv 1.1 type declaration opcodes to a 'is op type
declaration' switch in opcode.cpp.

source/opcode.cpp

@@ -255,6 +255,8 @@ int32_t spvOpcodeGeneratesType(SpvOp op) {
     case SpvOpTypeReserveId:
     case SpvOpTypeQueue:
     case SpvOpTypePipe:
+    case SpvOpTypePipeStorage:
+    case SpvOpTypeNamedBarrier:
       return true;
     default:
       // In particular, OpTypeForwardPointer does not generate a type,