regulator: Drop unnecessary struct member

The irq_flags from the regulator IRQ helper description struct was never
used. The IRQ flags are passed as parameters to helper registration
instead.

Remove the unnecessary struct field.

Fixes: 7111c6d1 ("regulator: IRQ based event/error notification helpers")
Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
Link: https://lore.kernel.org/r/5f6371e178453fa2b165da50452f7db4e986debb.1637736436.git.matti.vaittinen@fi.rohmeurope.com


Signed-off-by: Mark Brown <broonie@kernel.org>