mfd: intel_soc_pmic_crc: Use devm_regmap_add_irq_chip()

Use devm_regmap_add_irq_chip() to simplify the code.

While at it, replace -1 magic parameter by PLATFORM_DEVID_NONE when
calling mfd_add_devices().

Note, the mfd_add_devices() left in non-devm variant here due to
potentially increased churn while wrapping pwm_remove_table().

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20220801114211.36267-4-andriy.shevchenko@linux.intel.com