regmap: irq: dispose all virtual irq before removing domain

It is require to dispose all virtual irq of hwirq on chip
created on given irq domain before removing this irq domain.
Hence dispose all mapped irqs before deleting the irq domains
in regmap_del_irq_chip();

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Reviewed-by: Javier Martinez Canillas <javier@osg.samsung.com>
Tested-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>