twl4030: new-style driver conversion

twl4030: new-style driver conversion

More updates preparing for upstream merge of twl4030 driver:

 Basic fixes
   -	twl4030-core becomes a new-style I2C driver
   -	declare and use platform_data structure for that core
   -	stop hard-wiring the irq numbers
   -	check functionality that's really used:  I2C, not SMBus
 Cleanup:
   -	remove needless "client string"
   -	remove some fake "bool" types
   -	include catalog part numbers (TPS659{5,3,2}0)
   -	diagnostics should identify the driver!

To use this, all boards with these chips will need to declare this chip
when they declare their active I2C busses (done in a separate patch).

NOTE:  the TWL4030_IRQ_* symbols still need to vanish, along with other
global resource assignments associated with these chips.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Tony Lindgren <tony@atomide.com>