This patch restores libata.noacpi support to libata-acpi.c.
There are broken optional control methods for ATA controller devices in the
real world.  The libata.noacpi has been used for a long time as a
workaround to deal with issues caused by the broken ASL codes.
1. The "noacpi" option is introduced by the following commit:
   commit 11ef697b
   Date: Thu, 28 Sep 2006 11:29:01 -0700
   Subject: libata: ACPI and _GTF support
2. The "noacpi" option is renamed to "libata_noacpi" by the following
   commit:
   commit d7d0dad6
   Date: Wed, 28 Mar 2007 01:57:37 -0400
   Subject: [libata] Disable ACPI by default; fix namespace problems
3. Some of its logics are changed over time - becomes relying on the
   "acpi_handle" bound to the ATA devices since this commit:
   commit fafbae87
   Date: Tue, 15 May 2007 03:28:16 +0900
   Subject: libata-acpi: implement ata_acpi_associate()
4. The option is deleted by the following commit:
   commit 30dcf76a
   Date: Mon, 25 Jun 2012 16:13:04 +0800
   Subject: libata: migrate ACPI code over to new bindings
But the libata.noacpi setup is still left in the kernel without codes to
implement it.  So the deletion introduces a regression to the Linux.
This patch disables ATA_ACPI support at runtime by stopping acpi binding
on the ATA devices to fix this regression.
This patch is tested by booting a SATA x86-64 kernel or a PATA x86 kernel
with or without "libata.noacpi=1" kernel command line argument.
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>