Add Classes for Hardware Attributes

[tyler-gilbert]

Add classes for hardware attributes. For example:

class UartAttr {
public:
	u8 port() const { return m_port; }
	const uart_attr_t & attr() const { return m_attr; }
	mcu_pin_t tx() const { return m_attr.pin_assignment.tx; }
	mcu_pin_t rx() const { return m_attr.pin_assignment.rx; }
	mcu_pin_t cts() const { return m_attr.pin_assignment.cts; }
	mcu_pin_t rts() const { return m_attr.pin_assignment.rts; }


	void set_tx(const mcu_pin_t & pin){ m_attr.pin_assignment.tx = pin;}
	void set_rx(const mcu_pin_t & pin){ m_attr.pin_assignment.rx = pin;}
	void set_cts(const mcu_pin_t & pin){ m_attr.pin_assignment.cts = pin;}
	void set_rts(const mcu_pin_t & pin){ m_attr.pin_assignment.rts = pin;}
	void set_port(u8 p){ m_port = p; }
	void set_flags(u32 flags){ m_attr.o_flags = flags; }
	void set_freq(u32 f){ m_attr.freq = f; }
	void set_width(u32 w){ m_attr.width = w; }
private:
	u8 m_port;
	uart_attr_t m_attr;
};

Then add methods to sys::Cli to parse and handle attributes for each hardware type.