Convert to the new irq chip functions and cleanup the name space.

[ Guennadi reported: irq_data_get_chip_data is undefined. Yes, I screwed up. 
 it needs to be irq_data_get_irq_chip_data ]
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Cc: Dan Williams <dan.j.williams@intel.com>
LKML-Reference: <alpine.LFD.2.00.1103251220000.31464@localhost6.localdomain6>