ata: ahci_platform: Add ACPI _CLS matching

This patch adds ACPI supports for AHCI platform driver, which uses _CLS
method to match the device.

The following is an example of ASL structure in DSDT for a SATA controller,
which contains _CLS package to be matched by the ahci_platform driver:

  Device (AHC0) // AHCI Controller
  {
    Name(_HID, "AMDI0600")
    Name (_CCA, 1)
    Name (_CLS, Package (3)
    {
      0x01, // Base Class: Mass Storage
      0x06, // Sub-Class: serial ATA
      0x01, // Interface: AHCI
    })
    Name (_CRS, ResourceTemplate ()
    {
      Memory32Fixed (ReadWrite, 0xE0300000, 0x00010000)
      Interrupt (ResourceConsumer, Level, ActiveHigh, Exclusive,,,) { 387 }
    })
  }

Also, since ATA driver should not require PCI support for ATA_ACPI,
this patch removes dependency in the driver/ata/Kconfig.

Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/drivers/ata/Kconfig b/drivers/ata/Kconfig
index 6d17a3b..15e40ee 100644
--- a/drivers/ata/Kconfig
+++ b/drivers/ata/Kconfig
@@ -48,7 +48,7 @@
 
 config ATA_ACPI
 	bool "ATA ACPI Support"
-	depends on ACPI && PCI
+	depends on ACPI
 	default y
 	help
 	  This option adds support for ATA-related ACPI objects.