power: supply: bq24190_charger: Use i2c-core irq-mapping code

The i2c-core already maps of irqs before calling the driver's probe
function and there are no in tree users of
bq24190_platform_data->gpio_int.

Remove the redundant custom irq-mapping code and just use client->irq.

Cc: Liam Breck <kernel@networkimprov.net>
Cc: Tony Lindgren <tony@atomide.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Sebastian Reichel <sre@kernel.org>