Split the IRQ support out of twl4030-core.c into twl4030-irq.c,
including some minor tidy-ups and a note_interrupt() paranoia
in case of flakiness with some PIH interrupt.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Tony Lindgren <tony@atomide.com>