compat: backport IRQ namespace cleanup

compat: backport IRQ namespace cleanup

This backports this upstream patch:

commit a0cd9ca2b907d7ee26575e7b63ac92dad768a75e
Author: Thomas Gleixner <tglx@linutronix.de>
Date:   Thu Feb 10 11:36:33 2011 +0100

    genirq: Namespace cleanup

    The irq namespace has become quite convoluted. My bad.  Clean it up
    and deprecate the old functions. All new functions follow the scheme:

    irq number based:
        irq_set/get/xxx/_xxx(unsigned int irq, ...)

    irq_data based:
         irq_data_set/get/xxx/_xxx(struct irq_data *d, ....)

    irq_desc based:
         irq_desc_get_xxx(struct irq_desc *desc)

    Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>