gpiolib: acpi: Convert ACPI value of debounce to microseconds

gpiolib: acpi: Convert ACPI value of debounce to microseconds

BugLink: https://bugs.launchpad.net/bugs/1966056
[ Upstream commit 660c619b9d7ccd28648ee3766cdbe94ec7b27402 ]

It appears that GPIO ACPI library uses ACPI debounce values directly.
However, the GPIO library APIs expect the debounce timeout to be in
microseconds.

Convert ACPI value of debounce to microseconds.

While at it, document this detail where it is appropriate.

BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=215664
Reported-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Fixes: 8dcb7a15a585 ("gpiolib: acpi: Take into account debounce settings")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>