drivers: acpi: acpi_apd: Remove unused device property "is-rv"

drivers: acpi: acpi_apd: Remove unused device property "is-rv"

Initially "is-rv" device property is added for 48MHz fixed clock
support on Raven or RV architecture. It's unused now as we moved
to pci device_id based selection to extend such support on other
architectures. This change removed unused code from acpi driver.

Signed-off-by: Ajit Kumar Pandey <AjitKumar.Pandey@amd.com>
Reviewed-by: Mario Limonciello <Mario.Limonciello@amd.com>
Link: https://lore.kernel.org/r/20211212180527.1641362-3-AjitKumar.Pandey@amd.com
Signed-off-by: Stephen Boyd <sboyd@kernel.org>