MAX77650 MFD driver uses regmap_irq API but doesn't select the required
REGMAP_IRQ option in Kconfig. This can cause the following build error
if regmap irq is not enabled implicitly by someone else:

    ld: drivers/mfd/max77650.o: in function `max77650_i2c_probe':
    max77650.c:(.text+0xcb): undefined reference to `devm_regmap_add_irq_chip'
    ld: max77650.c:(.text+0xdb): undefined reference to `regmap_irq_get_domain'
    make: *** [Makefile:1079: vmlinux] Error 1

Fix it by adding the missing option.

Fixes: d0f60334 ("mfd: Add new driver for MAX77650 PMIC")
Reported-by: Paul Gazzillo <paul@pgazz.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>