pinctrl: intel: Retain HOSTSW_OWN for requested gpio pin

The touchpad of the ASUS laptops E403NA, X540NA, X541NA are not
responsive after suspend/resume. The following error message
shows after resume.
 i2c_hid i2c-ELAN1200:00: failed to reset device.

On these laptops, the touchpad interrupt is connected via a GPIO
pin which is controlled by Intel pinctrl. After system resumes,
the GPIO is in ACPI mode and no longer works as an IRQ.

This commit saves the HOSTSW_OWN value during suspend, make sure
the HOSTSW_OWN mode remains the same after resume.

Signed-off-by: Chris Chiu <chiu@endlessm.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>